John Rodgers Meigs (February 9, 1842 – October 3, 1864) was an officer in the Union Army during the American Civil War. He was the son of Brigadier General Montgomery C. Meigs, the Quartermaster General of the United States Army. He participated in the First Battle of Bull Run, and later testified in the court-martial trial of an officer involved in the retreat from the battle. He attended the United States Military Academy, where he was an acting assistant professor of mathematics and graduated first in his class in June 1863. He was lauded by Secretary of War Edwin M. Stanton for strengthening the defenses of Baltimore, Maryland; was an engineer and acting aide-de-camp on the staff of Brigadier General (Volunteers) William W. Averell; was Chief Engineer of the Shenandoah Valley for the D