Which regiment did J.R.R. Tolkien join during the First World War?

J.R.R. Tolkien joined the Lancashire Fusiliers during the First World War.

After graduating from Oxford in 1915, Tolkien was commissioned as a second lieutenant in the Lancashire Fusiliers. He served with the 11th Battalion, which was part of the British Army’s expeditionary forces on the Western Front. In 1916 he took part in the Battle of the Somme.

Tolkien contracted trench fever and was sent back to England for treatment. He spent much of the remainder of the war in Britain, where he performed administrative and training duties. Most of the close friends who had formed the T.C.B.S. literary group died in the war, an experience that deeply affected him.

It is reasonable to connect the war’s landscapes, loss, and fellowship themes with Tolkien’s fiction, but specific one-to-one claims that particular characters represent individual soldiers are often overstated. The documented military fact is his service in the Lancashire Fusiliers.