Sibree, a scrum-half, started playing first-class rugby with Court Hill in 1903–04 and then joined Kensington. When the Kensington club folded, Sibree moved on to Harlequins, where he was mentored by England halfback Adrian Stoop. He gained three England caps himself across 1908 and 1909.[3]
In World War I, Sibree served with the Artists Rifles in France and after receiving commission was gazetted to the Norfolk Regiment, gaining promotion to captain in 1916. He was subsequently awarded a Military Cross, for gallantry shown leading his company under machine-gun fire, while wounded, in addition to another instance when his company captured 100 prisoners.[2]
