 After the war, he also served as the Commander of the 79th Field Artillery Regiment, which in 1951 became part of the NATO force present in Germany Lahaie then opened a new military college in Canada, becoming the first Commandant of the Royal Military College Saint-Jean when it opened in 1952.The Government of Canada, under Prime Minister Louis St. Laurent, decided to create a bilingual military college in the province of Quebec.Newly promoted Colonel Lahaie was entrusted with the opening of the new military college with the first Officer Cadets set to enter the college November 15, 1952.