Montesquieu, Charles Louis de Secondat, baron de la Brède et de
Charles Louis de Secondat Montesquieu, baron de la Brède et de (shärl lwē də səkôNdä´ bärôN´ də lä brĕd ā də môNtĕskyü´), 1689–1755, French jurist and political philosopher. He was councillor (1714) of the parlement of Bordeaux and its president (1716–28) after the death of an uncle, whom he succeeded in both title and office. He gained a seat in the French Academy in 1728. His Persian Letters (1721) brought him immediate fame. In these letters, supposedly written by Persian travelers in Europe and by their friends, he satirized and criticized French insititutions. In 1734 he produced a scientific historical study of the rise and fall of Rome, Considérations sur les causes de la grandeur des Romains et de leur décadence. His greatest work, The Spirit of Laws (1748), is a comparative study of three types of government—republic, monarchy, and despotism—and shows John Locke's influence on Montesquieu. Its main theories are that climate and circumstances determine the form of governments and that the powers of government should be separated and balanced in order to guarantee the freedom of the individual. Written with brilliance of style, it had great historical importance and influenced the formation of the American Constitution.
See biography by R. Shackleton (1961); studies by J. R. Loy (1968), M. Hulliung (1977), and T. L. Pangle (1989).