2/5th Battalion, East Lancashire Regiment.
Awarded the Military Cross in the London Gazette of 26 July 1918.
Grey was a native of Burnley, Lancashire.
The citation for his Military Cross reads, "For conspicuous gallantry and devotion to duty during a long period of constant fighting, when he continually rallied men of various units and brought them into action. His splendid courage, determination, and resource during a very trying period were most marked, and set a fine example to all."