CAULAINCOURT, ARMAND AUGUSTIN LOUIS, MARQUIS DE (1772-1827), French general and diplomatist, was born at Caulaincourt on Dec. 9, 1772, of a noble family. He early entered the army, did not emigrate in the revolution, but was de prived of his grade as captain in 1793, and served in the ranks. In 1795, through the protection of L. Hoche, he became captain again, was colonel in the Army of the Rhine in 1799-1800, and after the peace of Luneville (1801) was sent to St. Petersburg (Leningrad) to negotiate an understanding between Russia and France. On his return he was named aide-de-camp of the First Consul. He was employed to seize some agents of the English government in Baden in 1804, which led to the unfounded accusation that he was concerned in the arrest of the duc d'Enghien. He received the title of duke of Vicenza (1808). Napoleon sent him in 1807 as ambassador to St. Petersburg (Leningrad), where Caulaincourt tried to maintain the alliance of Tilsit, and succeeded in main taining the peace for some years. He accompanied Napoleon dur ing the invasion of Russia, from which he had in vain sought to dissuade him. During the last years of the empire, Caulaincourt was charged with all the diplomatic negotiations. He signed the armistice of Pleswitz, June, 1813, represented France at the con gress of Prague, in August, 1813, at the congress of Chatillon in Feb., 1814, and concluded the treaty of Fontainebleau on April 10, 1814. When Napoleon returned from Elba, he became minister of foreign affairs. After the second Restoration, Caulaincourt's name was on the proscription list, but it was erased on the personal intervention of Alexander I. with Louis XVIII.
Caulaincourt's memoirs appeared under the title of Souvenirs du duc de Vicence in 1837-40.
See A. Vandal, Napoleon et Alexandre (1891-95) ; Tatischeff. Alexandre Ier et Napoleon (1892) ; H. Houssaye, 1814 (1888) and 1815 (1893) ; N. Mikhailovich, Les Relations diplomatiques de la Russie et de la France, . . . 1805-1812 (1905).