Chapter 4: Life of the Empire

4.1 Internal management of the empire

4.1.1 Laws

The Roman Empire had an internal administration that might seem strange looking to the modern eye. The right to be judged according to Roman law was granted only to Roman citizens, whereas all other people living within the borders of the empire who were non-citizens judged according to their own laws. By the time of Augustus, Roman citizenship, which carried special political rights and opportunities to advance one’s career, was granted to all the freemen of Italy. Women and underage children were not citizens and were fully under the authority of the head of family.

Roman citizens also included legionaries and citizens (and their descendants) who settled outside of Italy but still within the empire. This covered only penal and civil law. The latter covered the extremely important right to property, the basis that grounded the right to a military career and political advancement. Basically the individual rights of a free citizen were understood on the grounds of his right to property. In fact freedom itself, as we saw, could be lost due to unpaid debts or gained by buying it back, as a slave from a master.

Besides the Roman citizens of the empire, all other people were judged according to their own laws. This of course created immense confusion, of which the most famous example is that surrounding the life and death of Christ, who according to the Evangelical tradition was presented to the Roman governor by the Jewish persecutors. Then the Roman governor refused to implicate himself in this affair and famously “washed his hands of it,” arguing in line with the agreement of the time that a Jew had to be judged by Jewish laws. In a controversy that was to last centuries, the Romans argued that the proper administration of the territory was based on the careful management of this distance between Roman and local laws.

In fact most parts of the Eastern Empire already had well-established codes of law and juridical procedures[1]. In general, it was Roman policy to respect the regional tradition or “law of the land” and to regard local laws as a source of legal precedent and social stability[2]. The compatibility of Roman and local law was thought to reflect an underlying ius gentium, the “law of nations” or international law regarded as common and customary among all human communities[3]. This concept is extremely important as it opened the way to the future idea of a “natural law” that was to play a crucial role in the development of social order in the early phases of modernity. If the particulars of provincial law conflicted with Roman law or custom, Roman courts heard appeals, and the emperor held final authority to render a decision.

The situation was different in the west, which was considered “underdeveloped”, if we want to use a modern term, by the Roman invaders, unlike the east where Roman generals were held in awe by the local ancient civilizations. In the west, law had been administered on a highly localized or tribal basis, and private property rights may have been a novelty of the Roman era, particularly among Celtic peoples. Roman law facilitated the acquisition of wealth by a pro-Roman elite who found their new privileges as citizens to be advantageous, something that secured the stability of the newly acquired lands[4].

The extension of universal citizenship to all free inhabitants of the empire in 212 by emperor Caracalla required the uniform application of Roman law, replacing the local law codes that had applied to non-citizens. Diocletian’s efforts to stabilize the empire after the Crisis of the Third Century included two major compilations of law in four years, the Codex Gregorianus and the Codex Hermogenianus, to guide provincial administrators in setting consistent legal standards[5]. The crisis was also known as the Military Anarchy or the Imperial Crisis (235–284), a period in which the empire nearly collapsed under the combined pressures of invasion, civil war, plague, and economic depression.

The pervasive exercise of Roman law throughout Western Europe led to its enormous influence on the Western legal tradition, reflected in the continued use of Latin legal terminology in modern law.

The law, clearly, covered the individuals in their economic and social transactions (civil law) and in their breach of social and state norms. But there was practically no systematic rule for the territorial administration of the empire. These were to be imported centuries later from China through the Jesuits’ work.

4.1.2 Taxes and territory

There were however, taxes. The typical tax rate paid by individuals ranged from 2 to 5%[6]. The fiscal code was extremely complicated, putting together a system of direct and indirect taxes, some paid in cash and some in kind. Taxes might be specific to a province or to kinds of properties, such as fisheries or salt-evaporation ponds; they might be in effect for a limited time. Tax collection was justified by the need to maintain the military, and taxpayers sometimes got a refund if the army captured surplus booty. In-kind taxes were accepted from less-monetized areas, particularly those who could supply grain or goods to army camps. The chaos in the management of taxes and their indirect link with the military, who were the primary beneficiary of the taxation, implied a confusion and inconsistency in the management of the military and of the territory.

The primary source of direct tax revenue was individuals, who paid a poll tax and a tax on their land, construed as a tax on its produce or productive capacity. Supplemental forms could be filed by those eligible for certain exemptions; for example, Egyptian farmers could register fields as fallow and tax-exempt depending on flood patterns of the Nile. Tax obligations were determined by the census, as in early republican Rome. The census required each head of household to appear before the presiding official and provide a headcount of his household, as well as an accounting of property he owned that was suitable for agriculture or habitation.

A major source of indirect tax revenue was the portoria, customs and tolls on imports and exports, including among provinces, which were administered as different territories, thus pushing for the separation of different spaces ruled by different and competing generals. Special taxes were levied on the slave trade. Toward the end of his reign, Augustus instituted a 4% tax on the sale of slaves, which Nero shifted from the purchaser to the dealers, who responded by raising their prices. An owner who manumitted a slave paid a “freedom tax,” calculated at 5% of the value.

An inheritance tax of 5% was assessed when Roman citizens above a certain net worth left property to anyone but members of their immediate families. Revenues from the estate tax and from a 1% sales tax on auctions went toward the veterans’ pension fund (aerarium militare).

Low imperial government taxes helped the Roman aristocracy increase their wealth, which equaled or exceeded the revenues of the central government. An emperor sometimes replenished his treasury by confiscating the estates of the “super-rich,” but in the later period, the resistance of the wealthy to paying taxes was one of the factors contributing to the collapse of the empire. Another factor was some of the super-rich were competing for power with wealthy neighboring generals and were vying to get their friends installed as emperor. Moreover, as we saw, In Roman society wealth and military standing were mostly one thing. Wealthy people were or had been also military, so they could exert some clout to protect their properties

An annexed territory became a province in a three-step process: making a register of cities, taking a census of the population, and surveying the land. Further government recordkeeping included births and deaths, real estate transactions, taxes, and juridical proceedings. In the first and second centuries, the central government sent out around 160 officials each year to govern outside Italy. Among these officials were the “Roman governors,” as they are called in English: either magistrates elected in Rome who in the name of the Roman people governed senatorial provinces; or governors, usually of equestrian rank, who held their imperium on behalf of the emperor in provinces excluded from senatorial control, most notably Roman Egypt. A governor had to make himself accessible to the people he governed, but he could delegate various duties. His staff, however, was minimal: his official attendants (apparitores), including lictors, heralds, messengers, scribes, and bodyguards; legates, both civil and military, usually of equestrian rank; and friends, ranging in age and experience, who accompanied him unofficially.

Other officials were appointed as supervisors of government finances. Separating fiscal responsibility from justice and administration was a reform of the imperial era. Under the republic, provincial governors and tax farmers could exploit local populations for personal gain more freely. Equestrian procurators, whose authority was originally “extrajudicial and extra-constitutional,” managed both state-owned property and the vast personal property of the emperor (res privata). Because Roman government officials were few in number, a provincial citizen who needed help with a legal dispute or criminal case might seek out any Roman perceived to have some official capacity, such as a procurator or a military officer, including centurions and down to the lowly stationarii or military police.

4.2 The imperial grand strategy

In the early phase of the empire, there was no demarcated imperial frontier and no system of fixed defense, nor were the legions stations in fortresses as in later decades, as Luttwak noted[7]. “Indeed they were not defensive positions at all… Throughout this period, the control of internal insurgency presented a far more difficult problem than the maintenance of external security vis-à-vis Parthia, whose power was the only ‘systemic’ threat to Rome, and then only on a regional scale.”

Colonies, where Roman legionaries were stationed outside of the empire’s borders, were a system to spread Roman influence but also for legionaries to defend their new hometowns in the event of an attack, while waiting for the arrival of the imperial troops. But they were also a system of prevention of attacks and consolidation of Roman presence. The Roman Limes “described a route of penetration cut through hostile territory rather than a ‘horizontal’ frontier, and certainly not a fortified defensive perimeter.” The absence of a perimeter of defense was key to the imperial security system of the time. The further consolidation of Roman power was helped by the presence of client states and tribes, who towed the Roman line in fear of retaliation.

The lack of clearly marked borders also meant the lack of a clearly marked territory to manage and from which to exact taxes and levy people for the imperial army. Yet, what from the Chinese point of view was a lack of firmly centralized authority, able to concentrate power and resources in times of need, was made up for by the ability for nimble reactions to what after all were not concentrated and existential threats.

In fact, “all of this changed by the time of Hadrian. The limits of empire were by then demarcated very precisely, so that all could tell exactly what was Roman and what was not.” This line of defense proved over the centuries to have many weak points and overall to be unmanageable. This observation had been the common analysis of Western military strategists in modern times. However, Luttwak reevaluated the Roman strategy of defense. “Defensive systems should instead be evaluated in relative terms: their cost in resources should be compared to their military ‘output.’ Further, the value of defensive systems must be assessed in terms of the type of threat they are intended to counter.”

In fact this economic principle led to what was a “conflict of priorities between the societal and logistic costs of delayed interception on the one hand and the strategic advantages of the greatest feasible preliminary concentration of forces on the other that resulted in the cyclical nature of the imperial strategy.”[8]

The tribal incursions would probe Roman defenses. If the defense was successful, the area and the logistic base would be stronger against future incursions. If the defense was not successful, incursions would be deeper and stronger, and Roman troops would be called in from other areas, which in turn would be weakened opening potential risks. In time foreign raids gave way to occupation of territory and the idea of defense in depth within the empire, where logistics favored the legionaries against the invaders.

This was coupled with the issue of sea security. Whereas the Mediterranean and the Black Sea were guaranteed safety because of Roman control of the surrounding land and naval superiority, the channel and the northern coasts were a different story. Here a few pirate raiders could cause immense direct and indirect damage to the adjoining lands. Raiders could create havoc and destruction in the local cities and force costly defensive measures. Both could prove very expensive for the empire.

In the third century, the empire withdrew along lines which were considered more defensible. This may well be because the Barbarians at the gate had become stronger but an overall change came about. A deep “elastic defense” of the later third century was replacing the shallow defense on the provincial level, and then fortifications had to be changed so that they could sustain resistance and protect lines of communication. Fortifications were beginning to be not only a show of power for the enemy and assembly camps for troops, as they were until the second century, but real defense pieces where Roman soldiers were to protect themselves.

Emperors became generals who had to command troops in the field against domestic and external threats. If he was not successful, he was soon replaced. The armies of the late empire were becoming much larger that in the early phases, but even so they could not hope to defend exclusively the vast and porous borders of the empire: “the enemy could be intercepted and often defeated, but only after he had done his worst. On the other hand, the centralized field armies could serve to protect the power of the soldier-emperors who controlled them.”

This in turn was bound to create a conflict with the civilian population, who did not feel protected by the imperial army against the invading Barbarians and thus grew estranged from Rome. The civilians were pressed by the constant threat of violence of the Barbarian invasions and the demands of taxes from the imperial authority.

We can divide the situation in two phases. First, there was a central Roman authority with tribal laws internally and client states abroad. Then came a second phase, with consolidation of power internally and client states absorbed outside it. This led to the idea of accepting war within the imperial borders, and it created vast indefensible frontiers and an unstable domestic situation with the Barbarians loosely assimilated and deep within Rome.

As Luttwak put it, “The new system provides no disposable surplus of military power either for offensive use or for diplomatic cohesion, deterrent or compellent. The difference is that the third system no longer has a surge capability either, since the enemies of the empire are no longer kept on the defensive by forward defense tactics: Instead they are only contained. When the containment forces are reduced to master ad hoc field forces, penetrations occur and the Antonine remnants of a capacity to generate the image of power for the purposes of political suasion is irrevocably lost. It follows that diplomatic relationships with external powers must reflect the local balance of forces—which cannot always favor the empire in every sector of the perimeter.

“With this the output and input of the system are finally equated. The level of security provided becomes directly proportional to the amount of resources expanded on the army and on frontier fortification. The great economy of force that made the unitary empire a most efficient provider of security is lost. From now on it merely enjoys certain modest economy of scale over the alternative of independent regional states. And these economies of scale are not large enough to compensate for much administrative inefficiency and venality. In the end, the idea and the reality of the unitary empire is sustained no longer by the loci of the elective security but only by the will of those who control the empirical power, and by immense fear of the unknown.”

All of this made the empire crumble. But it was not only this.

4.3 The double pressure: the undefeatable Barbarians and the unmanageable empire

As we saw in the previous section, each of the three strategies of defense had its faults and the last was eventually to doom the empire, but internally and externally there were also problems with strategic defense that would pile up.

On the east there was the empire of Parthia, Persians who were to be a constant pressure on the Roman Empire until they were vanquished by the Turks coming from the steppes. They were also the necessary passage to the profitable, although not fundamental, trade between the Mediterranean and the Indian and Chinese subcontinents. The pressure they placed on the richest part of the empire, the east, was strategically impossible to defeat.

Even if the Romans were to be able to conquer the Parthian Empire, as Alexander did in the fourth century BC, they would have to confront even more difficult enemies, like the fearsome Indian kingdoms or the warring Central Asian tribes. That is, the Roman conquest of Parthia would bequeath not more but less security to the empire, with longer and less defensible lines of communications and more and more diverse population to include in an already extremely fragmented empire. The problem, in fact—distinct from that of Alexander and of the future Mongol hordes—was not pushing the legions far away for the glory and possible plunder but holding onto the conquered lands. But holding on to these lands would be extremely costly and could further compromise the empire overall.

An even worse predicament faced the Romans on different borders. To the north and the west there were no empires or organized states to conquer and absorb wholesale, but there were loosely organized tribes without important cities to defend or a strong territorial basis. They could withdraw when the Romans advanced and advance when the Romans moved back. Even in the period of Rome’s massive strength, they would not pose an existential threat to the empire, but because of their relative economic weakness compared to the wealth of Rome, they were dependent on Rome’s gifts, trade, and plunder.

Rome tried a variety of measures to pacify them, but overall their absorption within the empire would further stretch the empire’s defenses and economy, while keeping them out of the empire would constantly prod them to get more out of the imperial system. Also, bordering tribes would gain more because of the immediate access to Rome whereas farther tribes would benefit less and thus would try to approach Rome, creating pressure on the Roman borders and competition and instability outside the borders.

Lastly, the geography of the empire was extremely weak. The whole northeast was open to a variety of enemies. Only the Sahara desert in the south provided a natural barrier against massive attacks from Africa. This was compounded by massive internal problems and exploded in the Crisis of the Third Century.

Starting on March 18, 235, with the assassination of the Emperor Alexander Severus, the Roman Empire sank into a 50-year civil war. The rise of the bellicose Sassanid Dynasty in Parthia posed a major threat to Rome in the east. Demonstrating the increased danger, Emperor Valerian was captured by Shapur I in 259. His eldest son and heir-apparent, Gallienus, succeeded him and took up the fight on the eastern frontier. Marcus Cassianius Latinius Postumus, the governor of the German provinces, rebelled; he attacked Colonia and killed the local Roman officials loyal to the emperor. In the confusion that followed, an independent state known as the Gallic Empire emerged. Its capital was modern Trier, and it quickly expanded its control over the German and Gaulish provinces and over all of Hispania and Britannia. It had its own senate and consuls. It maintained Roman religion, language, and culture, and was far more concerned with fighting the Germanic tribes than other Romans.

However, in the reign of Claudius Gothicus (268 to 270), large expanses of the Gallic Empire were restored to Roman rule. At roughly the same time, several eastern provinces seceded to join the Palmyrene Empire, under the rule of Queen Zenobia.

In 272, Emperor Aurelian finally managed to reclaim Palmyra (in modern Syria, its remains have been recently destroyed by the Islamic State) and its territory for the empire. With the east secure, his attention was turned to the west, taking the Gallic Empire a year later. The Gallic army was swiftly defeated and the empire was reunited.

But the crisis more than any other event highlighted the difficulties in managing an empire so vast with many different threats requiring very diverse responses. The external borders were mostly stable for the remainder of the Crisis of the Third Century, although between the death of Aurelian in 275 and the accession of Diocletian ten years later at least eight emperors or would-be emperors were killed, many assassinated by their own troops.

Under Diocletian, the political division of the Roman Empire began. It was an admission that the unified empire was unmanageable and the nature of the empire required two very different structures, one for the east, one for the west. The Mediterranean, which the Romans had united in the third century in the Punic wars, was being pulled apart half a millennium later. In 285, Diocletian promoted Maximian to the rank of emperor and gave him control of the western regions of the empire. In 293, Galerius and Constantius Chlorus were appointed as their subordinates (Caesars), creating the First Tetrarchy. This system effectively divided the empire into four major regions and created separate capitals besides Rome as a way to avoid the civil unrest that had marked the third century. In the west, the capitals were Maximian’s Mediolanum (now Milan) and Constantius’ Trier. In the east, the capitals were Sirmium and Nicomedia. On May 1, 305, the two senior Augusti stepped down, and their respective Caesars were promoted to Augusti and appointed two new Caesars, thus creating the Second Tetrarchy. To survive, the empire had given up total unity.

4.4 Social and economic crisis of the empire

The empire grew quite rapidly and in its early phases of expansion created a huge surplus of wealth (treasures looted from conquered countries), cheap labor (the prisoners of war turned to slaves), and new land (the conquered territories colonized by former Roman soldiers). Moreover the new unprecedented security of Mediterranean from pirates boosted trade along its coast, which was further moved by the search for new and exotic goods to improve the life and pleasures of newly rich Romans.

Silk arrived from China to dress rich Roman women in seductive semi-transparent robes. “Precious things from Da Qin [the Roman Empire] can be found there [in Tianzhu, the Kushan Empire in Northwestern India], as well as fine cotton cloths, fine wool carpets, perfumes of all sorts, sugar candy, pepper, ginger, and black salt.”[9]

Yet once the empire consolidated its territory, there was no new source of plundered gold and slaves to provide sudden boosts of wealth. The network of safe communication provided by the new Roman roads and maritime routes helped trade, and Italy became the center of this crossroads, plying the rich Romans with everything around from the world. Wealth in fact remained significantly higher in Italy compared to the rest of the empire, about 50% greater than the rest of the empire[10]. Wars and victory still conferred plunder, loot, and slaves but those possibly did not outstrip the actual cost of wars, as they never again brought in massive expansion of territory, slaves and land.

Meanwhile, taxation, as we saw, was quite low, about 5% of the gross income. Certainly rich and powerful people had ways to avoid taxation, and the tax system, delegated to local authorities, notoriously gave officials room to skim taxes due to Rome.

Finally since the Marian reforms, armies were not centralized bodies, but were personally loyal to the generals. We saw that the emperor was ultimately a general who commanded the loyalty of his troops, had a good bond with the former emperor, and, at the time of the former emperor’s demise, was able to impose his power through a conspiracy in Rome or simply by marching his troops against rival generals. This ultimately was the pattern started with the death of Julius Caesar.

This brought the empire to a constant state of war in which generals were leaders of power and economic enterprises, always on the prowl to increase the power and wealth of their own and their soldiers. Legionaries on the other hand agreed with this constant prowl for war as in it they had a route to social mobility, although it was very risky. Their guile and bravery could move them up the ranks of the legion and with each promotion came a greater share of the loot. Of course being born rich and powerful in the first place meant that some could start out having their own legions, which was a much safer and faster path to further wealth. But even that was no guarantee of final success. Wars were—and are—an extremely tricky and uncertain business, and many generals failed in their pursuit of money, power, and glory. Moreover, legions were notoriously fierce also because they could revolt against their general and kill him if he proved unworthy of his command.

Then we can see that besides the constant instability and uncertainty of the empire—a negative, if we wish to so characterize it—internal and external wars also provided a constant venue for social mobility and redistribution of wealth (poor legionaries could strike it rich by winning and looting richer legions)—a positive element for social stability. Yes, life with the threat of war was very risky, but possibly so was then life overall. People could be sold into slavery because of debt, and most people simply held on at survival level. In that case, life in a legion could provide an ambitious young man (the one who could go against the system if he did not have any other hope) with a possibility for change and hope—or provide the leaders with a chance to kill the troublemaker.

So the Roman Empire became and remained for many centuries one of the largest in history, with contiguous territories throughout Europe, North Africa, and the Middle East. They called it by the Latin phrase imperium sine fine (“empire without end”), expressing the ideology that neither time nor space limited the empire, similar to the concept of tianxia for the Chinese empire, all that is under heaven. Moreover, as in China, the emperor was the “son of heaven” (tianzi) and thus there was a religious coloring to his rule, as in the Rome of Virgil’s epic poem the Aeneid in which the limitless empire was granted by their supreme deity Jupiter[11]. This claim of universal dominion was renewed and perpetuated when the empire came under “Christian rule” in the fourth century[12].

The empire reached its largest expanse under Trajan (who reigned 98–117), encompassing an area of 5 million square kilometers that as of 2015 was divided among over forty different modern countries. The traditional population estimate of 55–60 million inhabitants accounted for between one-sixth and one-fourth of the world’s total population at the time[13] and made it the largest population of any unified political entity in the West until the mid-19th century. Recent demographic studies have argued that the population peaked at a range from 70 million to more than 100 million[14]. Each of the three largest cities in the empire—Rome, Alexandria in modern Egypt, and Antioch in modern Syria—was almost twice the size of any European city at the beginning of the 17th century.

Yet centuries of wars and exterminations exacted a huge toll on the soul of the people of the empire. Roman historian Tacitus looked at some of conquests and famously commented “to ravage, to slaughter, to usurp under false titles, they call empire; and where they make a desert, they call it peace.”

4.5 The empire’s classical legal system

Yet before looking at the deep spiritual crisis brought on by the endless war and strife, we may as well look also at a deeper structure that made the empire work peacefully: its laws and legal system. This is a significant legacy to the whole modern world, whose legal system is largely based on Roman laws. In about the first 250 years AD, roughly until the Crisis of the Third Century, Roman law and Roman legal science reached its greatest degree of sophistication. The law of this period is referred to as the classical period of Roman law.

The jurists worked in different functions as a growing technical body of consultants to officials who gained their position mostly thanks to military merits. They gave legal opinions at the request of private parties and advised magistrates who were entrusted with the administration of justice, especially the praetors, for whom they drafted the edicts in which they publicly announced at the beginning of their tenure how they would handle their duties and the formularies according to which specific proceedings were conducted. Some jurists also held high judicial and administrative offices themselves.

The jurists also produced all kinds of legal commentary and treatises that created a body of precedents that in turn guided the application of the law. Around 130 AD the jurist Salvius Iulianus drafted a standard form of the praetor’s edict, which was used by all praetors from that time onwards. This edict contained detailed descriptions of all cases in which the praetor would allow a legal action and in which he would grant a defense. The standard edict thus functioned like some kind of comprehensive legal code, even though it did not formally have the force of law. It indicated the requirements for a successful legal claim. The edict therefore became the basis for extensive legal commentary by later classical jurists. Among the new concepts and legal institutions developed by classical jurists that still today shape the legal mindset of the modern world are:

– A clear separation of the legal right to use a thing (ownership) from the factual ability to use and manipulate the thing (possession).

– The distinction between contract and tort as sources of legal obligations.

– The standard types of contract (sale, work, hire, services) regulated in most continental codes. The characteristics of each of these contracts were developed by Roman jurisprudence.

Furthermore, Gaius (around 160) invented a system of private law based on the division of all material into personae (persons), res (things) and actiones (legal actions). This system is still used now.

Roman law further established many concepts shaping laws and statecraft in modern societies.

The idea of a difference between ius civile, ius gentium, and the concept of ius naturale: The ius civile (“citizen law”, originally ius civile Quiritium) was the body of common laws that applied to Roman citizens and the praetores urbani, the individuals who had jurisdiction over cases involving citizens. The ius gentium (“law of peoples”) was the body of common laws that applied to foreigners and their dealings with Roman citizens. The praetores peregrini were the individuals who had jurisdiction over cases involving citizens and foreigners. Jus naturale was a concept the jurists developed to explain why all people seemed to obey some laws. Their answer was that a “natural law” instilled in all beings a common sense.

The concept of ius scriptum and ius non scriptum (written and unwritten law), respectively: In practice, the two differed by the means of their creation and not necessarily whether or not they were written down. The ius scriptum was the body of statutory laws made by the legislature. The laws were known as leges (“laws”) and plebiscita (originating in the Plebeian Council). Roman lawyers would also include in the ius scriptum the edicts of magistrates (magistratuum edicta), the advice of the Senate (Senatus consulta), the responses and thoughts of jurists (responsa prudentium), and the proclamations and beliefs of the emperor (principum placita). Ius non scriptum was the body of common laws that arose from customary practice and became binding over time.

Aside from the actual laws there were principles guiding the application of laws. There was the principle of division of ius commune and ius singulare. Ius singulare (singular law) was a special set of laws for certain groups of people, things, or legal relations—because of which it is an exception from the general principles of the legal system, unlike general, ordinary, law (ius commune). An example of this is the law about wills written by people in the military during a campaign, which are exempt from the solemnities generally required for citizens when writing wills in normal circumstances.

The most important principles were about the division between ius publicum (public law) and ius privatum (private law). Public law is to protect the interests of the Roman state, while private law should protect individuals against other individuals or the state. In Roman law, ius privatum included personal, property, civil, and criminal law; judicial proceedings were a private process (iudicium privatum); and crimes were private (except the most severe ones that were prosecuted by the state). Public law only began to include some areas of private law close to the end of the Roman state. Ius publicum was also used to describe obligatory legal regulations (today called ius cogens, the term is applied in modern international law to indicate peremptory norms that cannot be derogated from). These are regulations that cannot be changed or excluded by agreement among the parties. Those regulations that can be changed by the parties involved are today called ius dispositivum.

In a way higher than the laws themselves there was an unwritten set of guidelines and principles passed down mainly through precedent that helped in the interpretation of the laws, the mos maiorum (“custom of the ancestors”). These precedents actually regulated the exercise and deployment of power in the state. These concepts, which originated in the Roman constitution, live on in constitutions to this day. Examples include checks and balances, the separation of powers, vetoes, filibusters, quorum requirements, term limits, impeachments, the powers of the purse, and regularly scheduled elections. Even some lesser-used modern constitutional concepts, such as the block voting of the electoral college in the United States, originate from ideas found in the Roman constitution.

The constitution of the Roman republic was not formal or even official; it was after all defined as a “custom.” It was largely unwritten, and was constantly evolving throughout the life of the republic. Throughout the first century BC, the power and legitimacy of the Roman constitution was progressively eroding. Even Roman constitutionalists, such as Cicero, lost a willingness to remain faithful to it towards the end of the republic. When the Roman republic ultimately fell in the years following Mark Antony’s suicide, what was left of the Roman constitution died along with the Republic. The first emperor, Augustus, attempted to manufacture the appearance of a constitution that still governed the empire. The belief in a surviving constitution lasted well into the life of the Roman Empire because it was a form of legitimacy underpinning the constant strife and fights within and outside the empire.

In any case, possibly the main historical legacy of Roman law was the concept of private law. The Stipulatio was the basic form of contract in Roman law. It was in the format of question and answer and was about the measures to take in order to protect the legitimate right of possession of something, be it an object or an asset.

The precise nature of the contract was open to many possibilities. The rei vindicatio was, and still is, a legal action by which the plaintiff demands that the defendant return a thing that belongs to the plaintiff. It may only be used when plaintiff owns the thing, and the defendant is somehow impeding the plaintiff’s possession of the thing. The plaintiff could also institute an actio furti (a personal action) to punish the defendant. If the thing could not be recovered, the plaintiff could claim damages from the defendant with the aid of a condictio furtiva (a personal action). With the aid of the actio legis Aquiliae (a personal action), the plaintiff could also claim damages from the defendant.

For this it was also extremely important to define the status of the persons involved in the contract, as it gave different rights and obligations before the law. The individual could have been a Roman citizen (status civitatis) unlike foreigners, free (status libertatis) unlike slaves, have a certain position in a Roman family (status familiae) such as the head of the family (pater familias), or be some lower member, for instance alieni iuris, which lives by someone else’s law (that is, free foreigners in the Roman Empire). Two special status types were that of senator and emperor.

These differences were fundamental when things went awry and Romans went into litigation, which was the central part of the Roman law where everything came to fruition, in a way. The principles of litigation actually evolved over time. The history of Roman law can be divided into three systems of procedure: legis actiones, the formulary system, and cognitio extra ordinem. The periods in which these systems were in use overlapped one another and did not have definitive breaks, but it can be stated that the legis actio system prevailed from 450 BC (when the first Roman laws were imported from Greece, the laws of Solon) until about the end of the second century BC, the period of the civil wars. The formulary procedure was primarily used from the last century of the republic until the end of the classical period (c. 200 AD). The cognitio extra ordinem was in use in post-Classical times. Again, these dates are meant as a tool to help understand the types of procedures in use, not as a rigid boundary for when one system stopped and another began.[15]

During the republic and until later imperial period, the judge was usually a private person. He had to be a Roman male citizen. The parties could agree on a judge, or they could appoint one from a list, called the album iudicum. They went down the list until they found a judge agreeable to both parties, or if none could be found, they had to take the last one on the list.

No one had a legal obligation to judge a case. The judge had great latitude in the way he conducted the litigation. He considered all the evidence and ruled in the way that seemed just. Because the judge was not a jurist or a legal technician, he often consulted a jurist about the technical aspects of the case, but he was not bound by the jurist’s reply. At the end of the litigation, if things were not clear to him, he could refuse to give a judgment, by swearing that it wasn’t clear. Also, there was a maximum time to issue a judgment, which depended on some technical issues (type of action, etc.).

Later on, with the bureaucratization in the imperial period, this procedure disappeared, and was substituted with the so-called “extra ordinem” procedure, also known as cognitory. The whole case was reviewed by a magistrate in a single phase. The magistrate had obligation to judge and issue a decision, and the decision could be appealed to a higher magistrate.

All in all what the republic first and the empire later did was to expand the power of civil officials and private citizens to limit and constrain the use of force in their private matters. Laws were not simply an imposition of rules from above but a way to decrease friction and tension between individuals. It was in a way something to maintain the fabric of civil society, and thus only in the second phase had to do with the order of the state. One can see that in the role of private contracts, private litigation, and the private appointment of judges. The fact that individuals recognized the role of the law in regulating their own lives gave laws in Roman society an almost independent power and life of their own, largely autonomous from the ultimate imperial power. This was reinforced by the perception that laws had a natural origin and were based in common sense.

All these facts and the common and widespread acknowledgement of the life of laws contributed to an important consequence: the absolute power of the emperor itself had to find accommodation and legitimacy in the traditional system of laws; force by itself was not the total and absolute justification of power. The power of the Roman aristocracy, the Senate—although no match against the force of the legions—had to be considered and weighed by the emperor. On the other hand, ultimately the emperor could kill or imprison his opponents on trumped-up charges. The law at the end of the day was as harsh as legionaries’ brute force: dura lex sed lex (the law however harsh is the law).

All this excluded humanity and common feelings, which came back with a vengeance with the spread of new religions in the empire. These also brought a new way of looking at the world, something that eventually radically changed the empire.

4.6 The rise of new religions

Religion was not a strong element in Roman political and military expansion. As we saw, even laws spread slowly and gradually through the whole population. From the beginning, there was a syncretic attitude toward religion, slightly different from with laws but possibly along similar lines. The Roman traditional pantheon was soon assimilated to the Greek one, changing just the names: Jupiter to Zeus, Mars to Ares, et cetera. The same was done, for instance, with the Phoenician religion where, for instance, Baal was recognized as the local translation for Jupiter or Zeus. As the Romans extended their dominance throughout the Mediterranean world, their policy in general was to absorb the deities and cults of other peoples rather than try to eradicate them, since they believed that preserving local tradition promoted social stability[16].

All religions were included in the new tolerant Roman pantheon. The exceptions were those religions deemed subversive, and they were believed so because they provided an ideological glue for anti-Roman resistance. For instance, ancient Druidic beliefs held together Gallic uprisings, and the Jewish faith pushed forward Zealot’s fighters.

Yet with the first century AD, something new started spreading in empire. New faiths, coming mostly from the east, were not openly subversive of Roman rule, but neither were they easily assimilated to the Roman-Greek pantheon. Traders, legionaries, and other travelers brought home cults originating from Egypt, Greece, Iberia, India, and Persia. The cults of Cybele, Isis, Mithras, and Sol Invictus were particularly important[17]. Some of those were initiatory religions of intense personal significance, similar to Christianity, the religion that was to conquer them all. Curiously, Buddhism never reached the Mediterranean, as Christianity never really spread beyond the Asian steppes and highlands in antiquity.

In the beginning, however, the strongest of the new religions was the cult of Mithra, a mystery religion (involving various degrees of initiations) practiced from about the first to fourth centuries AD. The name of the Persian god Mithra (proto-Indo-Iranian Mitra), adapted into Greek as Mithras, was linked to a new and distinctive imagery. Writers during the Roman Empire referred to this mystery religion by phrases that can be anglicized as “mysteries of Mithras” or “mysteries of the Persians.” The mysteries were quite popular in the Roman military[18] and seem to have had a distinctive vision of the universe that scholars think followed the process of equinoxes and the study of distant constellations.

The surviving iconic scenes of Mithras show him being born from a rock, slaughtering a bull, and sharing a banquet with the god Sol, the Sun. No written narratives or theology from the religion survive, with limited information derived from inscriptions, and only brief or passing references in Greek and Latin literature. Interpretation of the physical evidence remains problematic and contested.

The Romans themselves regarded the mysteries as having Persian or Zoroastrian sources. Since the early 1970s, however, the dominant scholarship has noted dissimilarities between Persian Mithra-worship and the Roman Mithraic mysteries. The mysteries of Mithras are now generally seen as a distinct product of the Roman Imperial religious world.[19] In this context, Mithraism has sometimes been viewed as a rival of early Christianity. The central ritual was the slaying of a sacred bull, whose spilled blood was to elicit some kind of salvation. Here there are some similarities with Christian beliefs, where followers are asked to ritually share a sip of the blood Christ spilled to save humanity and thus be reunited with him in it.

Mithraism reached the apogee during the second and third centuries, spreading at an astonishing rate during the same period when Sol Invictus (“Unconquered God-Sun,” celebrated on the winter solstice, a day symbolically replaced by the celebration of the Christian Christmas) became part of the state pantheon. But Mithraism never became one of the state cults. By the fourth century this religion was quite dead. It is hard to understand why it died out. Certainly there was the repression of pagan cults by Christianity, which had in the meantime become a state religion[20].

However this may not be enough as pagan cults continued to prosper for centuries in the periphery of the empire. There is virtually no evidence for the continuance of the cult of Mithras into the fifth century. Curiously, the cult disappeared earlier than that of Isis, of Egyptian origin. Isis was still remembered in the Middle Ages as a pagan deity, but Mithras was already forgotten in late antiquity. It is possible that Mithras’ followers blended in with gnostic Christian groups, which paid great attention to the study of the sky.

With hindsight it is important is to note that the rise of Christianity was not unchallenged. Other new religions were vying for the hearts and minds of Romans at a time when the empire could not expand more and when a lot of blood was being spilled to hold on the empire. And the conditions for the rise of Christianity were set by the earlier spread of other cults, which shook the foundations of the traditional Roman pantheon and its religious views. Romans were looking for some other, deeper meaning in life, a need that was no longer satisfied with the beliefs and rituals of their own traditional gods and goddesses. Followers of Mithras looked to the stars for deeper truth.

Christians turned their attention to the previously unfathomed recesses of one’s conscience and claimed that there was something that gave people both immortality and salvation from the torments of life. They called it the “soul,” and in that soul, within the hearts of every one of us, may be a way out for the people of the empire who felt under siege from within and without.

4.7 The spread of early Christianity

The Roman Empire is deeply entwined with the very rise of Christianity out of the Jewish mainstream. The Gospels tell us that Jesus’ earthly parents, Joseph and Mary, were moving to Bethlehem to be registered in the imperial census ordered by emperor Augustus. In a detail that was played up in later history of Christianity God came on Earth at the time when Rome established the empire with its first Emperor. Some thirty years later, Jesus’ fate was decided by the Roman Governor Pilatus, who washed his hands of him, gave him up to the fury of the Jewish rabble, and yet had Roman soldiers put him on the cross, a very Roman execution system, used also for the rebellious slaves of Spartacus.

Early Romans found Christianity a new, disobedient, even atheistic sub-sect of Judaism: it denied all other forms of religion and was therefore considered a superstitio. But by the end of the Imperial era, Nicene Christianity was the one permitted Roman religio; all other cults were heretical or pagan superstitiones[21]. The first rise to notoriety of Christianity came just about 30 years after Jesus’ crucifixion. After the Great Fire of Rome in 64 AD, Emperor still used the Christians as convenient scapegoats who were later persecuted and killed. This means that Christians by then had already reached Rome from Palestine and had become a significant group. Christianity was spreading through the empire like wildfire, although they must have been still a minority otherwise they could not have been singled out.[22]

The persecution further helped their spread. Against the brutality of Rome, whose ferocity so far had conquered everybody, they presented a docile disposition to martyrdom. From that point on, Roman official policy toward Christianity tended toward persecution, something that it turned out to boost conversions rather than preventing them. The effect was possibly due to the Christian attitude of accepting and forgiving their executioners, rather than opposing and hating them. This apparently moved and converted their persecutors. During the various imperial crises of the third century, “contemporaries were predisposed to decode any crisis in religious terms,” regardless of their allegiance to particular practices or belief systems. Christianity drew its traditional base of support from the powerless, who seemed to have no religious stake in the well-being of the Roman state, and therefore threatened its existence[23].

The majority of Rome’s elite came to observe various forms of inclusive Hellenistic monism, which grew out of the old polytheistic tradition. Neoplatonism in particular accommodated the miraculous and the ascetic within a traditional Greek-Roman cultic framework. This spread of Hellenistic monotheism and the Hellenistic tradition that soon colored Christian theology and possibly helped Christian beliefs to make inroads in Roman society. Christians also saw these ungodly practices as a primary cause of economic and political crisis of the empire. They offered a loyalist’s way out of the earthly problems of the empire: if the people and the Emperor came to believe in the true God, the empire would be saved.

In the wake of religious riots in Egypt, Emperor Decius (249-251) decreed that all subjects of the empire must actively seek to benefit the state through witnessed and certified sacrifice to “ancestral gods” or suffer a penalty. Decius’ edict appealed to whatever common mos maiores might unite a politically and socially fractured empire and its multitude of cults; no ancestral gods were specified by name. The fulfillment of sacrificial obligation by loyal subjects would define them and their gods as Roman[24].

Later Emperor Valerian’s first religious edict (253-259) singled out Christianity as a particularly self-interested and subversive foreign cult, outlawed its assemblies, and urged Christians to sacrifice to Rome’s traditional gods. His second edict acknowledged a Christian threat to the imperial system, not yet at its heart but close to it, among Rome’s knights and senators.

Yet the next forty years were peaceful; the Christian Church grew stronger and its literature and theology gained a higher social and intellectual profile, due in part to its own search for political toleration and theological coherence. Origen of Alexandria, Egypt (184/185–253/254) discussed theological issues with traditionalist elites using a common Neoplatonist frame of reference. The Christian churches were disunited. Paul of Samosata, Bishop of Antioch, was deposed by a synod of 268 for “dogmatic reasons—his doctrine on the human nature of Christ was rejected—and for his lifestyle, which reminded his brethren of the habits of the administrative elite.”

Aurelian (270-75) reverted to a new official form of the unitary cult of Sol Invictus that was supposed to bring back the faith and determination in the Roman legions, but it did not work. In 295, a certain Maximilian refused military service; in 298, a centurion Marcellus renounced his military oath. Both were executed for treason; both were Christians. As the crisis in the legions during the republic was due to social friction and possibilities for advancement in the army and in society, in the imperial times religion played a greater role in undermining the army’s morale and fighting spirit. Some time around 302, a report of ominous haruspices in Diocletian’s domus and a subsequent order of placatory sacrifice by the entire military triggered a series of edicts against Christianity[25]. The first, in 303 AD, “ordered the destruction of church buildings and Christian texts, forbade services to be held, degraded officials who were Christians, re-enslaved imperial freedmen who were Christians, and reduced the legal rights of all Christians… [Physical] or capital punishments were not imposed on them” but soon after, several Christians suspected of attempted arson in the palace were executed. The second edict threatened Christian priests with imprisonment, and the third offered them freedom if they performed sacrifice. It was the largest, most systematic—but also possibly the last—persecution against Christians. In fact, the results were uneven and thus they helped the further spread of Christianity.

In some cases and in some places the edicts were strictly enforced. Some Christians resisted and were imprisoned or martyred. Others complied. Some local communities were not only predominantly Christian, but powerful and influential; and some provincial authorities were lenient, notably the Caesar in Gaul, Constantius Chlorus, the father of Constantine I. The Christians became stronger than ever. On his deathbed in 311, Diocletian’s successor Galerius revoked the persecutions and asked Christians to pray for him. “This meant an official recognition of their importance in the religious world of the Roman Empire, although one of the tetrarchs, Maximinus Daia, still oppressed Christians in his part of the empire up to 313.”[26]

Christianity had begun to convert emperors, and the whole political and religious game of the empire had changed.

With the abatement of persecution, St. Jerome acknowledged the empire as a bulwark against evil[27]. Against him, Donatus claimed that that the church must be a church of “saints,” not “sinners,” and that sacraments, such as baptism, administered by traditores were invalid. Donatists were rigorists and were one of the many dissenting voices and schisms in the early church.

A pontifex maximus (Rome’s supreme religious authority), Emperor Constantine I favored the “Catholic Church of the Christians” against the Donatists.

Constantine successfully balanced his own role as an instrument of the pax deorum with the power of the Christian priesthoods in determining what was, in traditional Roman terms, auspicious—or in Christian terms, what was orthodox. The Edict of Milan (313) redefined imperial ideology as one of mutual toleration. Constantine triumphed in a famous battle against competing Roman general Maxentius, who had a force twice as big as Constantine’s, which fought under the signum (sign) of the Christ (legionaries for the first time carried the sign of the cross on their shields).

Christianity was therefore officially embraced along with traditional religions and from his new eastern capital, Constantinople, Constantine could be seen to embody both Christian and Hellenic religious interests. His later direct intervention in church affairs proved a political masterstroke. Constantine united the empire as an absolute head of state, and on his death, he was honored as a Christian, imperial, and “divus[28].”

As Fabio Mini noted[29], at the time of his death he might not have been a Christian and Christianity might not have been the largest religion of the empire. Yet, Constantine’s financial and political support helped Christianity become solidified as an organized, majority religion that had substantial influence on the history of the Roman Empire. Constantine passed laws that prevented anyone from persecuting Christians, and because of this, the religion flourished. He built cathedrals all over the Roman Empire. Constantine also passed laws that gave Christians legal privileges, prevented them from being taxed, and thus accelerated conversions.

To unite Christianity and possibly put it under his thumb, Constantine called the first Christian general council in Nicea, which proved a founding moment for the unity and spread of Christianity in the empire and outside of it. Christianity had become the hegemonic cult of the empire.

After him Christianity was not without problems. Other emperors refused to accept the new beliefs. Some emperors were Arian Christian (who underscored the divinity of the Father in the trinity over that of the Christ and the Holy Spirit) as opposed to Nicene Christians (who stressed that the trinity was homoiousian, same substance/same being, between the three), but in any case the Roman had intertwined its destiny with that of Christianity.

[1] Ando, Clifford. “The Administration of the Provinces.” A Companion to the Roman Empire. Blackwell, 2010. 180. Fuhrmann, Christopher J. Policing the Roman Empire: Soldiers, Administration, and Public Order. Oxford University Press, 2012. 197, 214, 224.

[2] Garnsey and Saller. The Roman Empire: Economy, Society and Culture. 110. Ando, Clifford. “The Administration of the Provinces.” A Companion to the Roman Empire. Blackwell, 2010. 184–185.

[3] Bozeman, Adda B. Politics and Culture in International History from the Ancient Near East to the Opening of the Modern Age. 2nd edition. Transaction Publishers, 2010, 2nd edition. 208–20.

[4] Garnsey and Saller. The Roman Empire: Economy, Society and Culture. 110-111.

[5] Digeser, Elizabeth DePalma. The Making of a Christian Empire: Lactantius and Rome. Cornell University Press, 2000. 53.

[6] Ando, op. cit. p. 187.

[7] Luttwak, E. The Grand Strategy of the Roman Empire. 18–19. All quotes in this section are from this book and so is the main thrust of the argument.

[8] Luttwak, op. cit. p. 144 and following.

[9] Hou Hanshu as quoted in Hill, John E. Through the Jade Gate to Rome: A Study of the Silk Routes During the Later Han Dynasty, First to Second Centuries CE. BookSurge, 2009. 31.

[10] Lo Cascio, Elio and Paolo Malanima. “GDP in Pre-Modern Agrarian Economies (1–1820 AD). A Revision of the Estimates.” Rivista di storia economica. 25.3 (Dec. 2009), 391–420.

[11] Virgil. Aeneid. 1.278. Nicolet. Space, Geography, and Politics. 29. Mattingly, David J. Imperialism, Power, and Identity: Experiencing the Roman Empire. Princeton University Press, 2011). 15. Moretti, G. “The Other World and the ‘Antipodes’: The Myth of Unknown Countries between Antiquity and the Renaissance.” The Classical Tradition and the Americas: European Images of the Americas. Walter de Gruyter, 1993. 257. Southern, The Roman Empire from Severus to Constantine. 16.

[12] Prudentius (348–413) in particular Christianized the theme in his poetry, as noted by Marc Mastrangelo (The Roman Self in Late Antiquity: Prudentius and the Poetics of the Soul. Johns Hopkins University Press, 2008. 73, 203.) St. Augustine, however, distinguished between the secular and eternal “Rome” in The City of God. See also J. Rufus Fears (“The Cult of Jupiter and Roman Imperial Ideology.” Aufstieg und Niedergang der römischen Welt II.17.1 (1981). p. 136 and following.) on how Classical Roman ideology influenced Christian Imperial doctrine. Peter Fibiger Bang (“The King of Kings: Universal Hegemony, Imperial Power, and a New Comparative History of Rome.” The Roman Empire in Context: Historical and Comparative Perspectives. John Wiley & Sons, 2011.), and the Greek concept of globalism (oikouménē).

[13] Hopkins. The Political Economy of the Roman Empire. 184.

[14] Walter Scheidel. Population and demography, Version 1.0. Princeton/Stanford Working Papers in Classics, April 2006. 9.

[15] All this section is based on Jolowicz, H. F. Historical Introduction to the Study of Roman Law. Cambridge University Press, 1967.

[16] See also Isaac, Benjamin H. The Invention of Racism in Classical Antiquity. Princeton University Press, 2004, 2006. 449. Frend, W.H.C. Martyrdom and Persecution in the Early Church: A Study of Conflict from the Maccabees to Donatus. Doubleday, 1967. 106.

[17] Rüpke, Jörg, “Roman Religion: Religions of Rome.” A Companion to Roman Religion. Blackwell, 2007. p. 4 and following.

[18] Geden, A. S. Select Passages Illustrating Mithraism 1925. Kessinger Publishing, 2004. p. 51 and following. “Porphyry moreover seems to be the only writer who makes reference to women initiates into the service and rites of Mithra, and his allusion is perhaps due to a misunderstanding…..The participation of women in the ritual was not unknown in the Eastern cults, but the predominant military influence in Mithraism seems to render it unlikely in this instance.”

[19] Beck, Roger. “Mithraism”. Encyclopaedia Iranica, Online Edition. 2002. “For most of the twentieth century the major problem addressed by scholarship on both Roman Mithraism and the Iranian god Mithra was the question of continuity.”

[20] Martin, Luther H. and Roger Beck. Beck on Mithraism: Collected Works with New Essays. Ashgate Publishing, 2004. xiii. “However, the cult was vigorously opposed by Christian polemicists, especially by Justin and Tertullian, because of perceived similarities between it and early Christianity. And with the anti-pagan decrees of the Christian emperor Theodosius during the final decade of the fourth century, Mithraism disappeared from the history of religions as a viable religious practice.”

[21] Beard, M., J. North, and S. Price. Religions of Rome, Volume I and II, illustrated reprint. Cambridge University Press, 1998. See Vol 1, p. 225, citing Pliny the Younger, Letters, 10.96 and Vol. 2, 11.11a, citing Tacitus, Annals, 15.44.5.

[22] I owe this observation to Prof Ermis Segatti.

[23] Leppin, A Companion to Roman Religion. Ed. Jörg Rüpke. Wiley-Blackwell, 2007. 98

[24] For all of this see above, p. 100 and following.

[25] Lactantius. II.6.10.1-4. A date of 302 is regarded as likely. Eusebius also says the persecutions of Christians began in the army; see Eusebius. II.8.1.8.

[26] Leppin, op. cit. 103, citing Lactantius. De mortibus persecutorum. 34, 13; and Eusebius. Historia ecclesiastica. 8.17.3–10, 8.2.3–4.

[27] Jerome’s interpretations of imperial ceremony are heavily reliant on Eusebius’ polemical ecclesiastical-imperial history. Price, 203.

[28] Bunson, Matthew. Encyclopedia of the Roman Empire. Revised ed. 2002.

[29] Fabio Mini “I Guardiani del Potere”, il Mulino, 2014.