Osterhaus, Peter, 1823-1917

Peter Joseph Osterhaus was a Union general during the Civil War who served as chief of staff of the Military Division of West Mississippi, the command over Union forces in the Mississippi area at the end of the Civil War.

Born on January 4, 1823, in Koblenz, Prussia (modern-day Germany), Osterhaus attended a military academy in Berlin and became a Prussian army officer in the 1840s. He immigrated to the United States in the 1850s, following a series of revolutions in Prussia. After a short time in Illinois, Osterhaus settled to St. Louis, Missouri, which had a large German American population. Due to his experience and interest in military affairs, he took an active role training German American militia units in that city. When the Civil War broke out in 1861, Osterhaus volunteered for Union service. He rose to the rank of major of the Second Missouri Infantry Battalion (Union) and fought at the Battle of Wilson’s Creek in August 1861 in Missouri. Over the next two years, he rose in rank, commanding the Twelfth Missouri Infantry Regiment, and then being placed in charge of a division under Brigadier Franz Sigel, another German American officer. Osterhaus performed well at the Battle of Pea Ridge, Arkansas, in March 1862, resulting in his promotion to brigadier general.

Ostherhaus was hospitalized in late 1862 with malaria, he returned to the field in time to command Union soldiers during an assault on Fort Hindman, Arkansas, capturing the Confederate garrison there in January 1863. He then commanded a division of Ulysses S. Grant’s army during the Vicksburg Campaign, fighting at Champion Hill and Big Black River Bridge. He was wounded in the leg at the latter engagement. Following the campaign for Vicksburg, Osterhaus was sent to Chattanooga, Tennessee, where he suffered a battlefield defeat at Ringgold Gap, Georgia, in November 1863, but maintained his reputation as a capable combat commander. In 1864, he was part of William Tecumseh Sherman’s Union successful advance to Atlanta and earned promotion to major general that summer. In March 1865, Osterhaus was appointed chief of staff of the Military Division of West Mississippi, under Major General Edward Canby. The staff assignment did not preclude him from being campaigning in the field, as he participated in battles around Mobile, Alabama, including Spanish Fort and Fort Blakeley. He served a conspicuous role in the surrender of Confederate forces in the deep south, in particular being the highest ranking Union officer present when General Edmund Kirby Smith surrendered Confederate forces in the Trans-Mississippi Theater.

Osterhaus remained in the U.S. Army assisting with early Reconstruction and occupation duties in Mississippi until January 1866. He then received an appointment as U.S. Consul at Lyons, France. In the 1870s, he moved to Germany and received his German citizenship in 1879. He retained his connections to the United States, periodically visiting to attend reunions of the Grand Army of the Republic.

Osterhaus died in Germany on January 2, 1917. He had been married twice; first in 1846 to Matilda Born, who died in 1863, and then in 1864 to Amalie Anna Maria Born, who died in 1896. He had three children by his first wife, and one with his second wife. Osterhaus is buried in Koblenz, Germany.

(Wikipedia; Mark K. Christ, “Peter Joseph Osterhaus (1823-1917),” Encyclopedia of Arkansas; FindaGrave)

Peter Osterhaus belonged to the following social groups: