What was the name of the World War I regiment in which J.R.R. Tolkien served?

J.R.R. Tolkien served in the Lancashire Fusiliers during the First World War.

After graduating from Oxford, Tolkien was commissioned as a second lieutenant in the British Army. He served with the 11th Battalion of the Lancashire Fusiliers and went to France in 1916. He took part in the Battle of the Somme and later became ill with trench fever, a condition spread by lice.

Tolkien returned to England for treatment and was eventually declared unfit for general service. Most of the close friends who had formed his school literary group were killed in the war, an experience that deeply affected him. The landscapes, losses, and fellowship of wartime service are often discussed as part of the background to his later writing, although Middle-earth is not a direct retelling of the conflict.

The regiment is sometimes confused with Tolkien’s later academic affiliations. His military service came before his major Oxford professorships and before the publication of The Hobbit.