In November 1943, Vian returned to the UK as commander of Force J in preparation for D-Day and in January 1944, he was appointed commander of the Eastern Task Force (in ), supporting the D-Day landings in Normandy. He was appointed Companion of the Order of the Bath (CB) in the King's Birthday Honours, which coincided with the early stages of the invasion. After the success of the landings, he was appointed Knight Commander of the Order of the Bath (KCB) "for distinguished services in the planning and execution of the successful landings".
