Born in Auckland, New Zealand, 24 August 1881, son of Casement Aickin, merchant, and Elizabeth Mitchell Garde his wife. Aickin came of a medical family on both sides, for his mother was the daughter of Thomas Garde, MD and his grandfather Thomas Leland Aickin was MD of Trinity College, Dublin and FR

Educated at Wesley College and Ormonde College, University of Melbourne, where he was awarded a major scholarship, he was later at the Middlesex Hospital as a postgraduate. After qualification he worked as a general practitioner in Kyneton, and in 1908 as resident medical officer at the Alfred Ho