One of the ancient authors I have been teaching about this quarter in my discussion sections on the Roman Republic is the Roman historian Polybius. Although Polybius was a native-born Greek, who was captured and brought to Italy as a hostage after the Third Macedonian War, he was a great admirer of the Roman state and political system. Polybius lived during a time of dramatic change. For centuries prior the rise of the Roman Empire, the Mediterranean world had been divided between various powers situated in Europe, Near Asia, and Africa. However, in the span of little more than a century, beginning with the First Punic War in 264 BCE and ending with the Third Punic War in 146 BCE (the year that saw the destruction of both Carthage and Corinth), Rome managed to conquer the majority of the Mediterranean Sea, bringing an end to a number of powerful rival empires.
Polybius was a direct witness to many of these events, even traveling as a companion to the Roman general Scipio Aemilianus, who sacked Carthage in 146 BCE. During his lifetime, Polybius saw the final end of the Carthaginian Empire, the Macedonian Empire, and the independence of many Greek city-states. By the time of his old age, Rome had gone from merely controlling the Italian peninsula to being the undisputed mistress of the Mediterranean.
As a historian, Polybius wanted to know what had caused the Roman Empire to be so successful in defeating its Mediterranean rivals. To find these causes, Polybius needed to do more than merely tell a story-like narrative about Rome’s past wars. Instead, Polybius constructed his Histories to be a rigorous, critical investigation into the years spanning from 264-146 BCE, which examined the key issues and events that had led to Rome’s dominance over the Mediterranean.
A very interesting facet of Polybius’ history is that he does not merely provide a chronological narrative of Rome’s wars, but also includes tangent discourses about Roman customs and political institutions.
Perhaps the most influential portion of Polybius’ work is Book VI, which deals with the Roman Constitution. Polybius recognized that a major contributor to Rome’s success was the Roman political system. While the Greek peninsula had been continually divided between rival city-states, which often fluctuated between various systems of government, Rome had instead managed to produce a stable political system that had not only united the Italian peninsula but also conquered and maintained an overseas Mediterranean Empire. What was the key to Rome’s success?
Like other ancient historians and political scientists, Polybius identified three alternate systems of government that were practiced in the Mediterranean world: monarchy, aristocracy, and democracy . The etymology of these terms is as follows:
μόνος (“alone/sole”) + ἀρχή (“rule”) = μοναρχία (“sole rule,” i.e. “monarchy”)
ἄριστος (“best”) + κράτος (“power”) = άριστοκρατία (“rule of the best,” i.e. “aristocracy”)
δῆμος (“people”) + κράτος (“power”) = δημοκρατία (“rule of the people,” i.e. “democracy”)
Polybius saw strengths and weaknesses to each of these types of government. Monarchies allowed for an efficient and organized authority, since, rather than getting tangled in quarrels and debates over policies, the monarch had full authority to enact necessary change. However, monarchies also led to the abuse of power and restrictions on political freedom. Polybius argued that monarchies are inevitably replaced by aristocracies, when the rich finally become weary of living under a single ruler and instead set up a ruling body of the wealthiest and most competent citizens. Aristocracies too, however, were prone to corruption, since the rich would eventually no longer serve the interests of society as a whole and would instead enact policies that protected their own interests. Thus, Polybius maintained that aristocracies are eventually replaced by democracies, where each male citizen is given the right to vote and participate in government. Democracies also, however, were prone to corruption, when radical demagogues took over who would manipulate the capricious whims of the people and would direct policy towards disastrous ends. Once a democracy collapsed into anarchy (“no rule”), the chaos could only be stopped when a powerful man restored order and established himself as a monarch. That monarch, however, would eventually be replaced again by an aristocracy, which would be replaced by a democracy, and so on. Such was the cycle of governments.
Polybius recognized that the transitions between these governments could have destructive, destabilizing effects. The cycle would envelope whole cities and empires in repeated civil wars, constitutional changes, and long-term instability. No doubt Polybius saw this instability as a major reason for the Greeks’ internal conflicts and eventual defeat by a foreign empire. That foreign empire, however, Rome, did not seem to Polybius to suffer from the same problems within its political system. Instead, Rome had set a new example of political continuity that had remained stable for multiple centuries. How had Rome broken the cycle?
Polybius in Book VI discusses how the Romans had set up a mixed system of government. Rather than be torn between a cycle of monarchy, aristocracy, and democracy, instead the Romans had combined elements of all three of these types of governments. Rome had two Consuls who held supreme executive power (the monarchs), but also a Senate consisting of the most wealthy and experienced citizens (the aristocrats), as well as an Assembly that permitted each man and tribe to vote on policies and elect magistrates (the democrats). Through this tripodal division of powers, the Roman Constitution was able to serve the interests of all members of society, while also imposing checks and balances on each through having independent branches of authority.
This division, Polybius argued, was the key to the Romans’ success, since it allowed for the Roman state to have internal stability while they conquered their Greek rivals, who were always dis-unified due to oscillation in their governing systems.
The tripodal system of government described above has probably already struck a chord with many readers. What other system of government today likewise is based on a tripodal division of powers? The United States Constitution. When I first read Book VI of Polybius’ Histories, I couldn’t help but be reminded of the division of powers between the Executive, Judicial, and Legislative branches of the U.S. government. While not an exact parallel, the division of powers in the United States’ system is very similar, with a sole president having the chief executive authority, an elite and experienced body of judges serving as the ruling council of the judiciary (supreme court justices are likewise appointed for life, just as were Roman senators), and a popularly elected legislative body representing the will of the people.
The similarities between the constitutions of Rome and United States is hardly a coincidence. Many of the United States’ founding fathers had extensive Classical training in Greek and Latin literature. To quote Thomas Jefferson:
“To read the Latin and Greek authors in their original, is a sublime luxury … I thank on my knees, him who directed my early education, for having put into my possession this rich source of delight …” (Letter to Priestley, Jan. 27, 1800)
However, when I first studied Polybius I was not sure whether he had directly impacted the founding fathers’ ideas about the division of powers in a mixed government, or whether they had picked up the idea only indirectly from later authors (such as Montesquieu). Sure enough, however, after doing some research, I found this valuable article written by Marshall Lloyd that discusses Polybius’ influence on the founding fathers. By the time of the late-18th century CE, Polybius’ 2nd-century BCE Greek history had been reconstructed from the surviving Medieval manuscripts and published in various editions through the printing press. Many of the founding fathers had copies of Polybius’ Histories. As Mortimer Sellers (pg. 46) writes in American Republicanism: Roman Ideology in the United States Constitution:
“Americans understood the Roman constitution primarily through the writings of Polybius, readily available in four recent printings, and after [January of] 1787 in excerpts from Spelman’s translation, reproduced in John Adam’s Defense of the Constitutions of the United States of America.”
Likewise, the father of the United States Constitution, James Madison, quotes Polybius in The Federalist Papers No. 63 and in No. 47 discusses the division of powers extensively and its role in the U.S. government:
“The accumulation of all powers, legislative, executive, and judiciary, in the same hands whether of one, a few or many, and whether hereditary, self appointed, or elective, may justly be pronounced the very definition of tyranny.”
As Lloyd notes, “Here Madison reveals a Greek influence in his use of such terms as one, few, many, and tyranny.”
I just think it is interesting to see how influential Polybius’ Histories has been. Not only did Polybius perform a massive investigation in his own time into the causes of Rome’s successful conquest of the Mediterranean, but his inquiry into the strengths of the Roman Constitution has likewise influenced subsequent philosophers, political scientists, and statesmen. Furthermore, it’s also nice to see how my own field of Classics is still very relevant today. After all, many of the founding fathers were Classicists.
The Roman Republic was the the longest lasting republic in world history, surviving for approximately 450 years. While the United States has not even been a nation for that long, the U.S. Constitution is nevertheless the oldest constitution still practiced in the world today. The founding fathers studied past political experiments to find the strongest political system, and the Histories of Polybius was a major work that influenced both their thoughts and the founding of the nation that I live in today. It goes to show just how intellectually rigorous and influential some ancient historical works have been. Historians it turns out not only write about past events, but also shape our future.
 This is actually a somewhat simplified description of Polybius’ different political constitutions, since he actually identifies six (6.3.6). However, the additional three that Polybius adds are simply corrupted forms of the central three constitutions described above: tyranny, oligarchy, and mob rule. Polybius explains that not all monarchies are kingships, since some are tyrannies. Likewise, not all oligarchies are aristocracies, since aristocracy implies the rule of the best, whereas oligarchy only requires the rule of the few. Polybius also contrasts stable democracy with mob rule. However, these additional constitutions that Polybius names still follow the same structure of the rule of the one, verses the rule of the few, verses the rule of the many. It should also be noted that Polybius was not the first ancient author to discuss the concept of a mixed constitution between monarchy, aristocracy, and democracy. Aristotle likewise discusses the notion in his Politics (4.1293b); however, Polybius is famous for being an ancient author who specifically interpreted Rome’s constitution under a mixed constitutional model.