Francois Horace Bastien Sebastiani, count, a French soldier, born near Bastia, Corsica, Nov. 11, 1775, died in Paris, July 21, 1851. After several years' service, he became prominent in the Italian campaigns of Bonaparte, whom he aided in the coup d'état of the 18th Brumaire, and who after the battle of Austerlitz (1805) appointed him general of division. In 1802 he visited Constantinople to alienate Selim III. from Russia and England. In 1806 he went there again as ambassador, and thwarted English intervention; but the success of his mission was frustrated by the sultan's deposition. Subsequently he joined the army in Spain, from which he withdrew in May, 1810, after incurring Napoleon's displeasure by boasting too much of his exploits. In the Russian campaign of 1812, and in the battles of 1813 and 1814, he displayed great valor. On the first abdication of the emperor he joined the Bourbons, but went over to Napoleon after his return from Elba. In 1819 he was elected to the chamber of deputies, of which he remained a member for many years. Under Louis Philippe he became minister of marine in August, 1830, and of foreign affairs in November. His blind devotion to the king's peace policy led to his retirement in October, 1832, but in the following March he reëntered the cabinet as minister without a portfolio.

He finally withdrew, April 1, 1834, on the rejection by the chamber of his provisional indemnity treaty with the United States. He was ambassador to Naples in 1834-'5, and to London in 1835-'40, after which he was made a marshal. In 1847 his only daughter was murdered by her husband, the duke de Praslin.