Percy Allman-Smith went to a boarding school in Dovegrove, Birr, County Offaly and while a student in Trinity College Dublin, studying medicine, he was picked for the Irish Olympic hockey team for the 1908 London Olympic Games and played, as a forward, in Ireland’s two games. In addition to playing hockey for Trinity, Allman-Smith later played for Dublin based Three Rock Rovers Hockey Club, and was capped four times for Ireland. His brother Vincent Allman-Smith was an interprovincial hockey player and played tennis for Ireland from 1925-35, playing on the Irish Davis Cup team in 1930. After joining the British Army in 1912, in the Royal Army Medical Corps, Percy Allman-Smith had a long career as an Army doctor before retiring in 1949.