From his Wikipedia article:
He saw active service in the war, sustaining several wounds in close-quarter battle. His left hand was left virtually useless by wounds sustained on the Somme; his legs were riddled with shrapnel; he received a bayonet wound in the groin; and the lasting impacts of a blow to the head from a German soldier's rifle butt left him prone to blackouts after the war. He was medically discharged from the army with the rank of lance corporal in May 1917. He received the Silver War Badge having been honourably discharged from the army due to wounds received in the war, and was awarded the British War Medal and the Victory Medal for his service.