According to his attestation papers dated March 1, 1916 at Toronto, Charles Daniel Johnson of Mimico, Ontario was born on February 15, 1891 at Mimico, Ontario. He listed his mother, Elizabeth Johnson, Mimico, Ontario as his next of kin. He was a farmer and had no previous military experience. He was 25 years of age and stood 5 feet 9 1/2 inches tall. He had brown eyes, dark brown hair and a fresh complexion. He was a Methodist.
According to the 1911 census records he was the son of Alexander and Elizabeth Johnson. The 1914 Toronto City directory lists an Alex Johnson, occupation dairy, living on the east side of of Elizabeth Street.
His brother Cecil also enlisted.