Dallas J. Thompson was born in Armstrong Co., Pennsylvania, near Kittanning, on 20 March 1847, to Reverend John Gearhart Thompson and Katherine Gearhart. He attended public schools at Allegheny College; served in the Union Army during the entire Civil War; enlisted Sept. 17, 1861, for three years in Co. H, 78th Pennsylvania Infantry. His regiment was stationed on Lookout Mountain and fought in the Atlanta campaign and at Chattanooga. He mustered out with his company on 4 November 1864. After the war he worked for the postal service in Youngstown, Ohio; he died 20 September 1915.
From the description of Dallas J. Thompson Civil War diary and cartes-de-visite, 1864. (Pennsylvania State University Libraries). WorldCat record id: 669579462
