Often referred to as a soldier's soldier, Constantine spent his life in the army from the time he joined the
Royal Canadian Horse Artillery (or RCHA) in 1905, until he retired in 1943. He entered the Permanent Force in 1905. By the time that the
First World War broke out, he had become a captain. He was appointed
brigade major shortly after proceeding oversees with the
1st Canadian Division. He was promoted to
lieutenant colonel just before the
Battle of Vimy Ridge in 1917 and placed in command of the 5th Canadian Field Brigade. He rose to the command of an Artillery Brigade, winning the
Distinguished Service Order, or DSO, and bar and the Legion of Honour. He was made a Companion of the
Order of the Bath, or CB. After the war he held many important military posts, including O.C. of the Royal Canadian Horse Artillery. Following the First World War, he taught at the RMC then went to staff college in
England. He was appointed the 11th Commandant at the RMC (1925–30). During this period he consolidated the work of restoring it after the damages caused by the war. In 1925, Constantine was informed that the Department of Militia intended to expand the RMC over the next ten years so that it could handle three hundred cadets, a seven-month physical training course for officers and other ranks, equitation courses and special courses for the military training of officers of the Royal Canadian Navy, the Active Militia and the Royal Canadian Air Force. Summer training and accommodation was provided at the RMC for cadets who were candidates for the Permanent Force, the
Royal Canadian Navy and the
Royal Canadian Air Force. To accommodate the growth of the college, a new
mechanical engineering shop was built and equipped to release the space under Currie Hall for a
drafting room. Although he also recommended plans for the construction of
dormitory, mess and recreation facilities, the accommodation problem was not immediately resolved. The universities and professional societies, such as the Institute of Chartered Accountants of Ontario continued to recognize RMC courses and several members of the academic staff took measures to improve their academic qualifications. Although the Advisory Board recommended that RMC offer a bachelor of
military science degree or that civilian universities give a special bachelor of military science degree to RMC graduates who completed their degrees in civilian universities, the proposal was coldly received by the Deputy Minister and Chief of the General Staff. Although some ex-cadets recommended the addition of more humanities and cultural courses, specialization was eliminated. All cadets took the same subjects with a heavy emphasis on
mathematics, with the exception of third year specialization in chemical engineering 1924-29. During the 20s, between one quarter and a half of each RMC class went into regular military service in Canada or in Britain, particularly into the Canadian technical corps, the signals and the engineers. The Constantine Arena was named in Major-General Constantine's honour, who in addition to his distinguished service career was an outstanding sportsman,
hockey player and coach at the RMC. The arena was built in 1960 during a period of rapid expansion of the RMC. After leaving RMC, he served as district officer commanding at
Saint John, New Brunswick (1930). In 1934, he became adjutant-general in
Ottawa, Ontario. In 1938, he was the commanding officer of Kingston Ontario, Canada's largest military district. With the advent of war in 1939, he was sent to
Halifax, Nova Scotia. He died in
Kingston, Ontario, the day before his 71st birthday. ==Family==