 He was killed in battle at Tianjin, China during the Boxer Rebellion while commanding the 9th Infantry Regiment.Liscum joined the 1st Vermont Infantry in May 1861 to serve in the Union Army during the American Civil War and by June was on the front lines participating in the Battle of Big Bethel.In February 1863, he was made a lieutenant and was severely wounded at the Battle of Gettysburg in July of that year.