Which Oxford society did C.S. Lewis join as an undergraduate in 1917?

C.S. Lewis joined the Oxford University Officers’ Training Corps as an undergraduate in 1917.

Lewis entered University College, Oxford, in 1917 while the First World War was still being fought. Like many young men of his generation, he received military training through the Oxford University Officers’ Training Corps, commonly abbreviated as the OTC. He was commissioned in the Somerset Light Infantry and served on the Western Front.

Lewis arrived in France in November 1917 and fought in the trenches. He was wounded at the Battle of Arras in April 1918 and returned to England for recovery. His wartime experience influenced later reflections on suffering, friendship, and mortality, although his fiction should not be treated as a direct memoir of combat. The Oxford Union was a debating society, not the military-training organization he joined during his undergraduate period.