[3] His anonymously published The Spirit of Law (1748), which was received well in both Great Britain and the American colonies, influenced the Founding Fathers of the United States in drafting the U.S. Constitution.

Montesquieu was born at the Château de la Brède in southwest France, 25 kilometres (16 mi) south of Bordeaux.

His mother, Marie Françoise de Pesnel (1665–1696), who died when Charles was seven, was an heiress who brought the title of Barony of La Brède to the Secondat family.

[6][7] After the death of his mother he was sent to the Catholic College of Juilly, a prominent school for the children of French nobility, where he remained from 1700 to 1711.

[12] The Baron died in 1716, leaving him his fortune as well as his title, and the office of président à mortier in the Bordeaux Parlement,[13] a post that he held for twelve years.

England had declared itself a constitutional monarchy in the wake of its Glorious Revolution (1688–1689), and joined with Scotland in the Union of 1707 to form the Kingdom of Great Britain.

In April 1728, with Berwick's nephew Lord Waldegrave as his traveling companion, Montesquieu embarked on a grand tour of Europe, during which he kept a journal.

He went to England at the end of October 1729, in the company of Lord Chesterfield, where he was initiated into Freemasonry at the Horn Tavern Lodge in Westminster.

Outwardly he seemed to be settling down as a squire: he altered his park in the English fashion, made inquiries into his own genealogy, and asserted his seignorial rights.

He expounded the view in Considerations on the Causes of the Greatness of the Romans and their Decline, that each historical event was driven by a principal movement: It is not chance that rules the world.

Former Former Montesquieu is credited as being among the progenitors, who include Herodotus and Tacitus, of anthropology—as being among the first to extend comparative methods of classification to the political forms in human societies.

Indeed, the French political anthropologist Georges Balandier considered Montesquieu to be "the initiator of a scientific enterprise that for a time performed the role of cultural and social anthropology".

American founders studied Montesquieu's views on how the English achieved liberty by separating executive, legislative, and judicial powers, and when Catherine the Great wrote her Nakaz (Instruction) for the Legislative Assembly she had created to clarify the existing Russian law code, she avowed borrowing heavily from Montesquieu's Spirit of Law, although she discarded or altered portions that did not support Russia's absolutist bureaucratic monarchy.

[22] Montesquieu's most influential work divided French society into three classes (or trias politica, a term he coined): the monarchy, the aristocracy, and the commons.

All would be lost if the same man or the same body of principals, or of nobles, or of the people, exercised these three powers: that of making laws, that of executing public resolutions, and that of judging crimes or disputes between individuals.

Montesquieu devotes one chapter of The Spirit of Law to a discussion of how the England's constitution sustained liberty (XI, 6), and another to the realities of English politics (XIX, 27).

"[24] Another example of Montesquieu's anthropological thinking, outlined in The Spirit of Law and hinted at in Persian Letters, is his meteorological climate theory, which holds that climate may substantially influence the nature of man and his society, a theory also promoted by the French naturalist Georges-Louis Leclerc, Comte de Buffon.

By placing an emphasis on environmental influences as a material condition of life, Montesquieu prefigured modern anthropology's concern with the impact of material conditions, such as available energy sources, organized production systems, and technologies, on the growth of complex socio-cultural systems.

Philip M. Parker, in his book Physioeconomics (MIT Press, 2000), endorses Montesquieu's theory and argues that much of the economic variation between countries is explained by the physiological effect of different climates.

From a sociological perspective, Louis Althusser, in his analysis of Montesquieu's revolution in method,[25] alluded to the seminal character of anthropology's inclusion of material factors, such as climate, in the explanation of social dynamics and political forms.

[27] On Europe Day 2007, the Montesquieu Institute opened in The Hague, the Netherlands, with a mission to advance research and education on the parliamentary history and political culture of the European Union and its member states.