[1] A longtime professor at the University of Toronto and York University, he was a two-time winner of the Governor General's Award for English-language non-fiction, winning for The Unguarded Frontier: A History of American-Canadian Relations at the 1942 Governor General's Awards and for The War: Fourth Year at the 1944 Governor General's Awards.
[2] Originally from Charlottetown, Prince Edward Island,[2] McInnis served as an artilleryman with the Canadian Expeditionary Force in France during World War I.
Writing poetry in his spare time, he published the collections Poems Written at the Front (1918) and The Road to Arras (1920), and won the Newdigate Prize in 1925 for his poem "Byron".
[4] He taught history at the University of Toronto for several years[1] before becoming executive director of the Canadian Institute of International Affairs in 1951.
[1] He joined York University in 1960, becoming the institution's dean of graduate studies in 1964.