There is one Commonwealth War Grave in St Allen Churchyard:
PRIVATE JOHN HENRY TREMAIN
Service Number: 22759
Regiment & Unit/Ship: Duke of Cornwall's Light Infantry 12th Bn.
Date of Death: Died 28 May 1916 Age 31 years
Country of Service: United Kingdom
Son of William Tremain, of Zelah, Callestick; husband of Edith Godfrey (formerly Tremain), of 3, Tregurra Lane, Truro.