0SMOND, Rene Eustache, Marquis de (os-mong), French diplomatist, born in Port au Prince, Hayti, in 1751" died in Paris in 1838. He entered the military service in 1767, was transferred in 1776 as colonel of cavalry to France, and in 1788 was minister to the Hague. After the revolution of 1791 he was appointed by the Constitutionalists ambassador to St. Petersburg, but declined and emigrated to Italy, and Napoleon afterward made fruitless attempts to attract him into his service. After the return of Louis XVIII., Osmond was appointed ambassador in Turin, and in 1815 a peer of France and ambassador to London. He retired from service in 1819, and continued in the chamber of peers till the revolution of 1830.--His brother, Antoine Eustache, French bishop, born in Port au Prince in 1754; died in Nancy in 1823, studied in his native city, was graduated in the Sorbonne of Paris, ordained priest, and afterward became vicar-general of Toulouse and bishop of Comminges. During the revolution he emigrated to Spain, and afterward to England, but returned to France in 1801, became bishop of Nancy in 1802, and in 1810 archbishop of Florence, but resigned in 1814 to resume his see of Nancy, where he did much good. --Another brother, Marie Joseph Eustache, Viscount d', born in Port au Prince in 1756" died in Pontchartrain in 1839, was colonel of the regiment of Normandy when the revolution began, and emigrated with his family. After the return of Louis XVIII, he was promoted to major-general, became lieutenant-general in 1818, and retired in 1819.