James Grant Wilson and John Fiske, eds., “Osterhaus, Peter Joseph,” Appleton’s Cyclopaedia of American Biography (New York: D. Appleton and Company, 1900), 4: 603.
OSTERHAUS, Peter Joseph, soldier, b. in Coblentz, Germany, about 1820. He became an officer in the Prussian army, and subsequently emigrated to the United States, settling in St. Louis, Mo. At the beginning of the civil war he entered the National service as major of the 2d Missouri volunteers. He took part in the actions at Dug Springs and Wilson's Creek, was made colonel of the 12th Missouri regiment, commanded a brigade under Gen. John C. Fremont, and took part in the expedition of Gen. Samuel R. Curtis into Arkansas in pursuit of Gen. Sterling Price, leading a division at Pea Ridge. He was commissioned brigadier- general of volunteers on 9 June, 1862, and commanded a division at Helena, Ark., with which he participated in the capture of Arkansas Post, and subsequently in the siege of Vicksburg. He was engaged in the operations at Chattanooga and the battle of Mission Ridge as commander of the 1st division of the 15th corps, and in the Atlanta campaign, the march through Georgia, and the campaign of the Carolinas he commanded that corps, being promoted major-general on 23 July, 1864. At the surrender of Gen. E. Kirbv Smith he acted as chief of staff to Gen. Edward R. S. Canby. He was mustered out on 15 Jan., 1866, and in the same year went to Lyons, France, as U. S. consul. He now (1888) resides at Mannheim, Germany, where he is director of a manufacturing association.