He served in the American War of Independence under Rochambeau, and in 1789 was sent as deputy to the States-General by the nobles of the bailliage of Péronne. In the Constituent Assembly he formed with Barnave and Adrien Duport a sort of association called the "Triumvirate," which controlled a group of about forty deputies forming the advanced left of the Assembly. He presented a famous report in the Constituent Assembly on the organization of the army, but is better known by his eloquent speech on February 28, 1791, at the Jacobin Club, against Mirabeau, whose relations with the court were beginning to be suspected, and who was a personal enemy of Lameth. However, after the flight of the king to Varennes, Lameth became reconciled with the court. He served in the army as maréchal-de-camp under Luckner and Lafayette, but was accused of treason on August 15 1792, fled the country, and was imprisoned by the Austrians.
After his release he engaged in commerce at Hamburg with his brother Charles and the duc d'Aiguillon, and did not return to France until the Consulate. Under the Empire he was made prefect successively in several departments, and in 1810 was created a baron. In 1814 he attached himself to the Bourbonss, and under the Restoration was appointed prefect of Somme, deputy for Seine-Inférieure and finally deputy for Seine-et-Oise, in which capacity he was a leader of the Liberal opposition. He was the author of an important History of the Constituent Assembly (Paris, 2 vols., 1828-1829).
Of his two brothers, Théodore Lameth (1756-1854) served in the American war, sat in the Legislative Assembly as deputy from the department of Jura, and became maréchal-de-camp; and Charles Malo François Lameth (1757-1832), who also served in America, was deputy to the States General of 1789, but emigrated early in the Revolution, returned to France under the Consulate, and was appointed governor of Würzburg under the Empire. Like Alexandre, Charles joined the Bourbons, succeeding Alexandre as deputy in 1829.
See FA Aulard, Les Orateurs de l'Assemblée Constituante (Paris, 1905); also M Tourneux, Bibliog. de l'histoire de Paris (vol. iv., 1906, s.v. “Lameth “).
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