According to his attestation papers dated December 7, 1915 at Toronto, John Greenhalgh, Manchester Street, Mimico was born on January 15, 1894 in Blackburn, Lancs, England. He listed his mother Isabella Greenhalgh, 70 Kemp (?) Street, Blackburn, Lancs, England as his next of kin. He was a labourer and had no previous military experience. He was 21 years and 11 months of age and stood 5 feet 5 1/2 inches tall. He had blue eyes, brown hair and a fresh complexion. He was a member of the Church of England.
He was a Private in the 20th Battalion Canadian Infantry (Central Ontario Regiment) when he was killed on May 11, 1917. He died of his wounds at the No. 6 Casualty Clearing Station. He is buried in Barlin Communal Cemetery Extension, Pas de Calais, France.