According to his attestation papers dated June 12, 1917 at Windsor, Ontario, James Joseph O'Donnell of 1263 Ontario Street, Cleveland, Ohio, was born on November 13, 1888 in Mimico, Ontario. He listed his father, Thomas O'Donnell of Harold Street, Mimico as his next of kin. He indicated that he was a railway switchman and that he had no previous military experience. He was 28 years of age and stood 5 feet 7 inches tall. He had blue eyes, light brown hair and a fair complexion. He was Roman Catholic.
According to the 1921 Toronto City directory he was living with his father Thomas O'Donnell on Harold Street, Mimico.