Mr. Muir, b. Dec. 5, 1837, in Philadelphia, Pa. Enlisted August 8, 1861, in Company E, 15th Iowa volunteer infantry. Mustered into United States service Nov. 5, 1861, at Keokuk, Iowa, a private; promoted to first sergeant March 1, 1862. Was in the battle of Shiloh, Tenn., April 6 and 7, 1862; severely wounded in right leg. His regiment was brigaded with the 11th, 13th and 16th Iowa regiments, and known as Brocker's [sic, should be Crocker's] Iowa brigade, and attached to the 17th army corps, Army of the Tennessee. Participated in all the battles and sieges of this army, including battles of Iuka, Corinth, Vicksburg, Jackson and the Atlanta campaign. Oct. 3, 1862, severely wounded in head at battle of Corinth. Feb. 9, 1863, promoted to second lieutenant. Dec. 7, 1863, to first lieutenant. July 20, 1864, breveted captain, and July 22, 1864, major; same day taken prisoner at battle of Atlanta, Ga., and confined in Macon, Savannah and Charleston military prisons until exchanged, Sept. 29, 1864. Detached from his own command during winter of 1864-5, and served on staff of Brigadier General A. G. Malloy as assistant adjutant general. Dec. 15 and 16, 1864, was in the battle of Nashville, Tenn., and March 10, 1865, participated in battle of Kinston, N. C. March 16, 1865, rejoined his own command and assigned to duty on staff of Brigadier General A. Hickenlooper as assistant adjutant general. July 24, 1865, mustered out of service at Louisville, Ky., by reason of close of the war.
SOURCE: Charles Hutchinson Thompson, A Genealogy Of The Descendants Of John Thomson Of Plymouth, Mass., p. 136