Major General Malcolm Smith Mercer (1859 – 1916) served with The Queen's Own Rifles as a young man in the 1885 North-West Rebellion. By the outbreak of the First World War, he was a Lieutenant Colonel in command of the Regiment. He became the Officer Commanding the 3rd Canadian Division in December 1915. As General Officer Commanding, Mercer was killed in Flanders. He was the highest-ranked Canadian officer to be killed in action.