Martin Mahoney was born in 1893 in Mount Gambier, South Australia, and enlisted for the war on 14 August, 1914. He had already had some military training, having been one year with the Broken Hill Rifle Club and six months with the 82nd Regiment. His mother, Annie Mahoney, lived at 3 Wolfram St., Broken Hill and was his next of kin. He was by trade a labourer, 5' 10" tall, with a fair complexion, brown hair and blue eyes. By religion, he was a Roman Catholic.

His army record is very slight, but he was fighting at Gallipoli  on  18 August 1915 when he received a gunshot wound to his left foot. Although this was operated on, he was declared an invalid and shipped back to Australia. He was discharged from the army and went to live at 'Tolarno', Fitzroy St., St. Kilda, Victoria,. He was awarded a pension of one pound a fortnight.

There is no other information in his army record.