[4] From 1940 to 1942, Davies was a member of the staff of Flag Officer Liverpool; her tasked included encoding and decoding messages concerning the Royal Navy's fight against the German U-boats.
[2] In August 1943, Davies was selected to be part of the delegation accompanying Winston Churchill, the then British Prime Minister, to the Quebec Conference.
[2] She returned to the United Kingdom with the rest of the British delegation aboard HMS Renown; unusually for a woman, she was "actually established as a member of the ship's company" during the voyage.
[2] In October 1960, Davies was announced as the next Director of the Women's Royal Naval Service, in succession to Dame Elizabeth Hoyer-Millar.
[1][2] Davies married Roy Cavander Lancaster, a military officer formerly with the East Kent Regiment, at the Chapel of Gray's Inn on 28 March 1967.
In her final years, Dame Jean Davies Lancaster lived at Warren Park Nursing Home in Blundellsands, Merseyside.