Montesquieu was born at the Château de la Brède in southwest France, 25 kilometres (16 mi) south of Bordeaux.  His father, Jacques de Secondat (1654–1713), was a soldier with a long noble ancestry, including descent from Richard de la Pole, Yorkist claimant to the English crown.
Montesquieu, French political philosopher whose principal work, The Spirit of Laws, was a major contribution to political theory. It inspired the Declaration of the Rights of Man and the Constitution of the United States. Learn more about Montesquieu’s life and work.
Montesquieu was one of the great political philosophers of the Enlightenment. Insatiably curious and mordantly funny, he constructed a naturalistic account of the various forms of government, and of the causes that made them what they were and that advanced or constrained their development.
Montesquieu - Enlightenment, Spirit, Laws: During his travels Montesquieu did not avoid the social pleasures that he had sought in Paris, but his serious ambitions were strengthened. He thought for a time of a diplomatic career but on his return to France decided to devote himself to literature.
Montesquieu’s masterpiece is one of the most influential studies in the history of political theory and jurisprudence. Montesquieu envisioned The Spirit of Laws as a major work of law and politics, and he applied himself accordingly to its composition .
The Spirit of Law (French: De l'esprit des lois, originally spelled De l'esprit des loix  ), also known in English as The Spirit of [the] Laws, is a treatise on political theory, as well as a pioneering work in comparative law by Montesquieu, published in 1748. 
What was Montesquieu best known for? French political philosopher Montesquieu was best known for The Spirit of Laws (1748), one of the great works in
Charles-Louis de Secondat, baron de Montesquieu, (born Jan. 18, 1689, Château La Brède, near Bordeaux, France—died Feb. 10, 1755, Paris), French philosophe and satirist. Born into a noble family, he held public office in Bordeaux from 1714.
The genuine novelty of Montesquieu’s work is to be found in its terms of analysis and its theoretical focus— the relations of a society’s laws to its type of government, climate, religion, mores ( moeurs ,) customs ( maniéres ,) and economy.
Introduction. The first readers of Montesquieu (b. 1689–d. 1755) confronted the breadth of writings that extended into every domain, seeking to offer a global vision of human activities by means of the notion of relationship ( rapport) that outright rejects any artificial segmentation of the real.