How the ancient Roman Republic helped shape the system of government in the US?

Answer 1

The Roman Republic helped to shape the system of government of the US in an indirect way. It did so through the writings of a Greek philosopher and, above all, a French philosopher, rather than through Roman writings

The prominent 18th century French philosopher Montesquieu adopted the interpretation of the constitution of the Roman Republic by Polybius, an ancient Greek historian. Polybius, following the models of the political theory of Aristotle, argued that the Republic was a "mixed constitution" which combined element of three different political constitutions: monarchy (the consuls were like monarchs) aristocracy (he saw the senate as being aristocratic) and democracy (the vote of the popular assemblies). These three constitutions complemented each other and provided checks and balances on each other. They made up for the weakness on the others, balancing them, and also checked the power of the others, providing for stability and fairness. Montesquieu developed his concept of separation of powers from Polybius' theory. A stable and fair state should be divided into branches, each with separate and independent powers and areas of responsibility so that no branch has more power than the other branches and each one provided checks and balances on the others. However, the model which Montesquieu actually used was that of the British system and he proposed that the separate branches were to be a legislative, an executive, and a judiciary. These kinds of branches were modern concepts which were not derived from the Roman Republic, whose arrangements were different.

Montesquieu's concept of mixed constitution and separation of powers became popular among US scholars, who argued that mix government was the key characteristic of a republic. This led to the United States Constitution embodying the doctrine of separation of powers and the federal government being divided into three branches: the legislature (the bicameral Congress) the executive (the President) and the judiciary (the Supreme Court and other federal courts). James Madison, Alexander Hamilton and John Say, the authors of the Federalist papers, were admirers of the Roman Republic and wrote their papers under the pseudonym "Publius" in honour Pulbius Valerius Publicola, one of the founders of the Roman Republic.

Answer 2

The short answer is - Roman ideas shaped everything.

Consider this excerpt from Federalist paper #6, published in a newspaper for general readership: "Sparta, Athens, Rome, and Carthage were all republics; two of them, Athens and Carthage, of the commercial kind. Yet were they as often engaged in wars, offensive and defensive, as the neighboring monarchies of the same times. Sparta was little better than a well-regulated camp; and Rome was never sated of carnage and conquest."

Note that Alexander Hamilton doesn't see a need to give particular references and throws around the facts as already understood - that's because the nature of the ancient world was simply understood by everyone, most of everything educated people read at the time were Roman and Greek works, at least in translation, and more often than not the original Latin or Greek. There are a few reasons for that -

The English colonies inherited English law, and England was a part of the Roman Empire. There were many demographic changes through various invasions, but regardless, a thousand years later, on account of the retained history and the influence of the Catholic Church before Henry VIII created the Church of England, Latin was the language of law and the Roman Code was a basis for many principles of "common law", as Blackstone pointed out in the first compendium of English Law, published 1758,

Europe had been rocked by war for 150 years over the discovered trade routes to the new world and the east. England had been plagued by civil wars and revolution and the colonies themselves were under constant threat by Native Americans, foreign colonists, and even pirates in the south. So - the stories and histories of an empire which held the European continent for 400 years, more or less, was incredibly attractive. Gibbon published his "rise and fall of the roman empire" in 1776, and it is about as comprehensive as any modern history save some archeological details.

Also, modern written forms weren't yet as we know them today. There was the bible and some scientific and philosophical treatise, basically written lectures, but probably little considered worth reading besides the Roman and Greek classics until Henry Fielding came along in the 1740's. So when the educated were reading books, they were reading Cato, Catullus, Thucydides, and Julius Caesar. Homer would have been to Jefferson what Mark Twain was to a 20th century American. It's difficult to exaggerate the importance of the classics to the educated colonists who comprised the constitutional conventions.

The Roman government became corrupted and eventually became a military Dictatorship, but initially there was a people's assembly and a senate of oligarchs that served a real advisory role to the "first citizen" who executed the law. This is almost identical to the form of government the Founding Fathers adopted. The analogy to the judicial branch would be the priestly caste, which had some power to address the people, decide festivals and awards, and judge the politicians. The comparison can go on forever,

There is a book, "Greek and Romans bearing gifts: How the ancients influence the founding fathers", I haven't read it but it sounds right on point.