Cyril Baker was born on 29 November 1892 in Launceston, Tasmania, the son of John Baker and Mary Alberta Elizabeth Baker (née Stoneman) of 110, Elizabeth Street, Launceston, Tasmania. He enlisted in the Royal Australian Navy as a Boy Seaman in HMAS PROTECTOR on 19 October 1911 for a five year engagement. On joining he was reported to be five foot five and a half inches tall with dark hair, brown/green eyes and a dark complexion.

He was re-rated as an Ordinary Seaman on 17 October 1912, backdated to date of entry, and was credited with the difference in rate of pay. On 30 September 1912 he signed on for a further seven years to take his total engagement to twelve years from the age of eighteen. By the time that he signed on for the additional seven year engagement he had tattoos of a heart and a spear on his right forearm and a kangaroo and a flag on his left forearm.

On 22 January 1913 he was drafted to HMAS CERBERUS and was rated Ordinary Telegraphist. On 25 July 1913 he had qualified as, and had been rated as a Telegraphist. He remained in HMAS CERBERUS until 1 August 1913 and was then drafted to HMAS ENCOUNTER on the following day. A year later on 3 August 1914 Cyril Baker was drafted to HMAS PENGUIN.

It is unclear when he joined HMAS AE1 but he was serving in the submarine when it was lost off New Britain in the Bismarck Archipelago on 14 September 1914. His Next of Kin was listed as his mother, Alberta Baker, of Launceston, Tasmania. He is commemorated on the Plymouth Naval Memorial on Panel 4.