William Patrick Earles was born in Collingwood, Melbourne, in 1893. He was aged 22, living in Kerang and working as a labourer when he enlisted on 31 December, 1915. He gave as his next of kin his widowed mother, Bridget Earles, who was then living at 140 Simpson St., East Melbourne.

William Earles joined the 21st Battalion, 6th Brigade, a Victorian unit raised at Broadmeadows, and drawing its recruits from all over Victoria. The 21st was sent to Gallipoli in June, then evacuated in December, 1915, arriving in France to fight on the Western Front in March 1916. In April, it became the first Australian Battalion to commence active operations on the Wesstern Front.

William Earles embarked for Egypt on 8 May, 1915, on the 'Ulysses' and proceeded to join the battalion on 29 August. On 19 September, he suffered an accidental self-inflicted gunshot wound to his left hand and was evacuated to a hospital ship, then transferred to base at Imbros. From here, he was admitted to hospital at Heliopolos on 21 September. In November, he was again in hospital at Helowan, having had a circumcision, rejoining his unit on 28 December, 1915.

On 19 March, 1916, the 21st Battalion left Alexandria for Marseilles, disembarking on 26 March. From here, they proceeded to the Western Front. From 23 July - 2 September, they were deployed at Pozieres, engaged at first mainly in carrying duties, before taking part in the fight to overcome the German defences at Moquet Farm. It was here that William Patrick Earles died in action on 29 July, 1916, one of the 11,000 casualties suffered by the Australian forces at Pozieres.

William Patrick Earles was buried at Pozieres British Cemetery, Ouillers-La Boiselle, France in Plot 1, Row H, Grave 27. His name is listed on Panel 93 at the Australian War Memorial, Canberra.

His mother retired to the Convent of the Good Shepherd at Abbotsford following his death.