Complex sentence: He was promoted to captain of Company K in the same regiment November 28,1861, and served until March 23,1863, when he was discharged on account of wounds received in the second Battle of Bull Run.
Split into simpler sentences: He was promoted to captain of Company K in the same regiment on November 28,1861. He served until March 23,1863, when he was discharged on account of wounds received in the Second Battle of Bull Run.