Henri Baron Jomini, a French military historian, born at Payerne, canton of Vaud, Switzerland, March 6, 1779, died at Pussy, near Paris, March 24, 1869. He joined the French army in 1804 with the rank of major, and was soon made a colonel, serving as aide-de-camp and chief of staff to Marshal Ney in Germany and Spain. In 1805 he presented to Napoleon on the field of Austerlitz the first edition of his Traite des grandes operations militaires, ou Histoire critique et militaire des guerres de Frederic II. comparees d celles de la revolution (5 vols. 8vo, with an atlas, Paris, 1804-'5). In consequence of a misunderstanding with Ney in 1808, he resigned, and offered his services to the emperor Alexander; but Napoleon compelled him to return and accept the commission of brigadier general. In 1812 he was appointed governor of Wilna and then of Smolensk, and was of great service to the French army during the latter part of the disastrous retreat from Moscow. After the victory of Bautzen Ney asked for him the rank of general of division; but Berthier, who was unfriendly to him, put him under arrest on account of some trifling irregularities in his routine duties.

This treatment he deeply resented; and after the armistice of Plaswitz he left the French army and repaired to the headquarters of Alexander, who appointed him his aide-decamp. Sentence of death was passed against him as a deserter. The rumor that he betrayed the military plans of the French was wholly unfounded, according to Napoleon's own declaration. Jomini even declined taking an active part in the operations of the allied armies against France. In 1815 he accompanied the czar to Paris, and received the cross of the order of St. Louis from Louis XVIII. He tried, but in vain, to save the life of Ney. After sojourning in France to superintend the publication of his great work, Histoire critique et militaire des campagnes de la revolution de 1792 a 1801, written in conjunction with Col. Koch (15 vols. 8vo, Paris, 1819-'24), he returned to Russia in 1822, and was intrusted with the completion of the military education of the grand duke Nicholas, who on his accession to the throne retained him as his aide-decamp. He served in 1828 during the Russian war against Turkey, and organized in 1830 the Russian military academy. He then retired to Brussels, but hastened to St. Petersburg on the breaking out of the Crimean war.

He spent the last years of his life in Brussels and Passy. Besides the above mentioned works, which are the basis of his reputation as a military writer, his chief publications are: Principes de la strategic (3 vols. 8vo, Paris, 1818); Vie poli-tique et militaire de Napoleon, racontee par lui-meme au tribunal de Cesar, d' Alexandre et de Frederic (4 vols., 1827); Tableau analytique des principales combinaisons de la guerre et de leurs rapports avec la politique des etats (4th ed., St. Petersburg, 1836); Precis de l'art de la guerre, ou nouveau Tableau analytique des principales combinaisons de la strategic, de la grande tactique et de la politique militaire (1830; new ed., Paris, 1855); Precis politique et militaire de la campagne de 1815 (1839); Appendice au Precis la I histoire de la guerre (1849). The following translations of his works have appeared in the United States: "Art of War," by Capt. G. II. Mendell and Lieut. W. P. Craighill (Philadelphia, 1862); "Political and Military Life of Napoleon," by Maj. Gen. II. W. Halleck (4 vols. 8vo, New York, 1804); "Political and Military History of the Campaign of Waterloo," by Capt. S. V. Benet (New York, 1864); "Treatise on Grand Military Operations, and Art of War," by Col. S. B. Holabird (2 vols. 8vo, with atlas, New York, 1865).