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Influences

The U.S. Constitution was a federal one and was greatly influenced by the study of Magna Carta and other federations, both ancient and extant. The Due Process Clause of the Constitution was partly based on common law and on Magna Carta (1215), which had become a foundation of English liberty against arbitrary power wielded by a ruler. The idea of Separation of Powers inherent in the Constitution was largely inspired by eighteenth-century Enlightenment philosophers, such as Montesquieu and John Locke.

The influence of Montesquieu, Locke, Edward Coke and William Blackstone were evident at the Constitutional Convention. Prior to and during the framing and signing of the Constitution, Blackstone, Hume, Locke and Montesquieu were among the political philosophers most frequently referred to. Historian Herbert W. Schneider held that the Scottish Enlightenment was "probably the most potent single tradition in the American Enlightenment" and the advancement of personal liberties. Historian Jack P. Greene maintains that by 1776 the founders drew heavily upon Magna Carta and the later writings of "Enlightenment rationalism" and English common law. Historian Daniel Walker Howe notes that Benjamin Franklin greatly admired David Hume, an eighteenth-century Scottish philosopher, and had studied many of his works while at Edinburgh in 1760. Both embraced the idea that high-ranking public officials should receive no salary and that the lower class was a better judge of character when it came to choosing their representatives.

In his Institutes of the Lawes of England, Coke interpreted Magna Carta protections and rights to apply not just to nobles, but to all British subjects. In writing the Virginia Charter of 1606, he enabled the King in Parliament to give those to be born in the colonies all rights and liberties as though they were born in England. William Blackstone's Commentaries on the Laws of England are considered the most influential books on law in the new republic. Madison made frequent reference to Blackstone, Locke, and Montesquieu, all of whom were among the most prominent political theorists of the late eighteenth century.

Following the Glorious Revolution of 1688, British political philosopher John Locke was a major influence, expanding on the contract theory of government advanced by Thomas Hobbes, his contemporary. Locke advanced the principle of consent of the governed in his Two Treatises of Government. Government's duty under a social contract among the sovereign people was to serve the people by protecting their rights. These basic rights were life, liberty, and property.

Montesquieu's influence on the framers is evident in Madison's Federalist No. 47 and Hamilton's Federalist No. 78. Jefferson, Adams, and Mason were known to read Montesquieu. Supreme Court Justices, the ultimate interpreters of the constitution, have cited Montesquieu throughout the Court's history. (See, e.g., Green v. Biddle, 21 U.S. 1, 1, 36 (1823). United States v. Wood, 39 U.S. 430, 438 (1840). Myers v. United States, 272 U.S. 52, 116 (1926). Nixon v. Administrator of General Services, 433 U.S. 425, 442 (1977). Bank Markazi v. Peterson, 136 U.S. 1310, 1330 (2016).) Montesquieu emphasized the need for balanced forces pushing against each other to prevent tyranny (reflecting the influence of Polybius 's 2nd century BC treatise on the checks and balances of the Roman Republic). In his The Spirit of Law, Montesquieu maintained that the separation of state powers should be by its service to the people's liberty: legislative, executive and judicial, while also emphasizing that the idea of separation had for its purpose the even distribution of authority among the several branches of government.

The English Bill of Rights (1689) was an inspiration for the American Bill of Rights. Both require jury trials, contain a right to keep and bear arms, prohibit excessive bail and forbid " cruel and unusual punishments ". Many liberties protected by state constitutions and the Virginia Declaration of Rights were incorporated into the Bill of Rights. Upon the arrival of the American Revolution, many of the rights guaranteed by the Federal Bill of Rights were recognized as being inspired by English law. A substantial body of thought had been developed from the literature of republicanism in the United States, typically demonstrated by the works of John Adams, who often quoted Blackstone and Montesquieu verbatim, and applied to the creation of state constitutions.

While the ideas of unalienable rights, the separation of powers and the structure of the Constitution were largely influenced by the European Enlightenment thinkers, like Montesquieu, John Locke and others, Benjamin Franklin and Thomas Jefferson still had reservations about the existing forms of government in Europe. In a speech at the Constitutional Convention Franklin stated, "We have gone back to ancient history for models of Government, and examined different forms of those Republics... And we have viewed modern States all round Europe but find none of their Constitutions suitable to our circumstances." Jefferson maintained, that most European governments were autocratic monarchies and not compatible with the egalitarian character of the American people. In a 1787 letter to John Rutledge, Jefferson asserted that "The only condition on earth to be compared with... is that of the Indians, where they still have less law than we." In that same letter, Jefferson maintained that American government, with its Native American features, marked a great improvement over the European models.

American Indian history scholars Donald Grinde and Bruce Johansen claim there is "overwhelming evidence" that Iroquois Confederacy political concepts and ideas influenced the U.S. Constitution, and are considered to be the most outspoken supporters of the Iroquois thesis. The idea as to the extent of that influence on the founding, however, varies among historians and has been questioned or criticized by various historians, including Samuel Payne, William Starna, George Hamell, and historian and archaeologist Philip Levy, who claims the evidence is largely coincidental and circumstantial. The most outspoken critic, anthropologist Elisabeth Tooker, claimed the Iroquois influence thesis is largely the product of "white interpretations of Indians" and "scholarly misapprehension".

The laws of the Iroquois Confederacy were familiar to founders like James Monroe, Benjamin Franklin and Thomas Jefferson, and is said to have influenced their thinking during the founding era to one degree or another. John Napoleon Brinton Hewitt, who was born on the Tuscarora Indian Reservation, and was an ethnologist at the Smithsonian Institution 's Bureau of Ethnology is often cited by historians of Iroquois history. Hewitt, however, rejected the idea that the Iroquois League had a major influence on the Albany Plan of Union, Benjamin Franklin's plan to create a unified government for the Thirteen Colonies, which was rejected.