Commanding Officer 48th Highlanders of Canada 1930-1932
Commanding Officer 13th Battalion (Royal Highlanders of Canada)
Commanding Officer 1st Battalion Argyll and Sutherland Highlanders of Canada (Jamaica 1941-42)
Born in Toronto on 16 June 1891, Sinclair was a student at the University of Toronto and member of the Queen’s Own Rifles. After the outbreak of the Great War, he had joined the 48th Highlanders and was briefly attached to the 15th Battalion. He transferred to the 13th Battalion on arrival in Valcartier. By the end of the war, Sinclair had been four times wounded in action, twice mentioned in dispatches and awarded the Distinguished Service Order and the Military Cross. He pursued various business interests after the war and became commanding officer of the 48th Highlanders from 1930 to 1932. During the Second World War, he was selected to command 1st Battalion Argyll and Sutherland Highlanders on garrison duty in Jamaica and later served as an advisor to the Bermuda and was admitted to the Order of the British Empire (Military) in the grade of Officer int end of war Honours List in January 1946. He retired from the military in 1946 and died in Toronto in 1980.