Tag: McMahon (Martin T.)

On staffs of Gen. McClellan and Gen. Sedgwick.

Wikipedia says: Martin Thomas McMahon (March 21, 1838 – April 21, 1906) was an American jurist and a Union Army general during the American Civil War. He was awarded the United States military’s highest decoration, the Medal of Honor, for his actions at the Battle of White Oak Swamp. After the war, he held various legal and judicial positions in the state of New York. He briefly served as the Minister Resident to Paraguay and was a New York State Senator for four years.

…At the outbreak of the Civil War, he raised a company of cavalry and was given the rank of captain at the head of that unit. After learning that his company would not be sent to the front lines, he resigned his command and returned east, where he was appointed aide-de-camp to General George B. McClellan. McMahon remained with the Army of the Potomac throughout the war, eventually rising to the rank of lieutenant colonel. He served as aide de camp to William B. Franklin (May 1862- January 1863) and Chief of Staff and Assistant Adjutant General of the 6th Corps (1 January 1863 to August 1865), serving under John Sedgwick and Horatio G. Wright. McMahon was with 6th Corps commander John Sedgwick at Spotsylvania when Sedgwick was killed. McMahon was the author of Maj. Gen. John Sedgwick – In Memoriam (1885).

Decades after the end of the conflict, on March 10, 1891, he was awarded the Medal of Honor for his actions at the Battle of White Oak Swamp on June 30, 1862. His official citation reads: “Under fire of the enemy, successfully destroyed a valuable train that had been abandoned and prevented it from falling into the hands of the enemy.”

McMahon’s two older brothers were also officers in the war, both with the 164th New York Volunteer Infantry. John Eugene McMahon (1834–1863) commanded the 164th before being injured; he later died of these injuries. Middle brother James Power McMahon (1836–1864) took over the regiment and led it until his death at the Battle of Cold Harbor.

McMahon was mustered out of the volunteers on February 21, 1866. On January 13, 1866, President Andrew Johnson nominated McMahon for appointment to the grade of brevet brigadier general of volunteers, to rank from March 13, 1865, and the United States Senate confirmed the appointment on March 12, 1866. On March 16, 1866, President Johnson nominated McMahon for appointment to the grade of brevet major general of volunteers, also to rank from March 13, 1865, and the United States Senate confirmed the appointment on April 10, 1866.

He received a Doctor of Laws degree from St. John’s College, Fordham. He was New York City’s corporation counsel for two years before becoming the United States minister to Paraguay, a position he held from 1868 to 1869. After returning to the U.S., he served as the Receiver of Taxes in New York from 1873 to 1885 and then worked as a U.S. Marshal for four years. During this time he became connected with the National Soldiers’ Home, of which he would serve as president for several years.