In which 1916 battle was J.R.R. Tolkien’s service as a British Army officer interrupted by illness?

J.R.R. Tolkien’s service as a British Army officer was interrupted by illness during the Battle of the Somme.

Tolkien served as a second lieutenant in the Lancashire Fusiliers during the First World War. He went to France in 1916 and took part in the Somme offensive, one of the war’s largest and deadliest campaigns. He was later diagnosed with trench fever and returned to England for treatment.

The Battle of the Somme began on 1 July 1916 and continued until 18 November. Tolkien’s wartime experience, including the loss of close friends, influenced aspects of his later writing, although particular one-to-one identifications between real battles and fictional events should be treated cautiously.

The Somme is sometimes confused with Passchendaele, another major First World War battle. Passchendaele took place in 1917, after Tolkien had left active service in France.