Private Mullis was born in Avon Dassett in 1876. Before enlistment he was a farm labourer. His family consisted of Ruth his wife and four children.

He enlisted, aged 36, in the Royal Engineers at Coventry on 10th December 1916. He was classified A1 fitness. During his service he qualified as a stevedore.

He was posted to France with the British Expeditionary Force and transferred to the 25th Royal Warwickshire Regiment.

Private Mullins was demobilised on 8th March 1919. He received the British Medal and the Victory Medal.