William Barker was born 19 July 1909, the son of Alfred Barker. In 1939 he married Margaret Beirne with whom he had one son and one daughter.

Barker was employed in Foreign Office in 1943 and held a number of positions including First Secretary, Prague, 1945; Foreign Service Officer, Grade 7, Senior Branch of Foreign Service, 1946; Chargé d’Affaires, Prague, 1947. He transferred to Moscow in August 1947 and was granted rank of Counsellor in December 1948. Barker was then Counsellor and Chargé d’Affaires in Oslo, 1951; Consul-General, Boston, Massachusetts, September 1954; Counsellor, Washington, 1955; Minister, Moscow, 1960-63; Fellow, Center for International Affairs at Harvard University, 1963-64; Assistant Under-Secretary of State, Foreign Office, 1965-66; Ambassador to Czechoslovakia, 1966-68. He was Bowes Professor of Russian at the University of Liverpool from 1969-76. He died on 8 January 1992.