Whittaker, the son of Richard and Lavina, was born in Radnorshire, Wales, UK, and at the age of seventeen came to Australia on the ship Euripides in 1914. He had been working as a farm labourer at Nullamanna, near Inverell NSW when he enlisted at Liverpool in April 1915, listing his sister, Mrs. L. Moseley as next of kin.
He joined the Divisional Signal Company 3, Section 2 and departed Australia for Egypt on HMAT A39 Port Macquarie in June 1915. He served at Gallipoli where he became ill and was sent for treatment to hospital at Malta. In March 1916 he went to France, and later had leave in England in June 1917. He returned to Australia in 1919 and was discharged. In 1967 he was living at Wentworthville, Sydney. Whittaker died at Concord Repatriation Hospital, Sydney in 1974.
Whittaker's name is recorded on the Inverell Honor Roll.