After leaving Palestine in February 1947, Barker returned to England, where he succeeded Lieutenant General Sir Oliver Leese, a fellow student at Camberley, as GOC of Eastern Command, a big step-down after his previous jobs. On 15 November 1948 he was promoted to the four-star rank of general (with seniority backdated to 3 October 1946). Shortly after being made Knight Commander of the Order of the Bath (KCB) on 2 January 1950, he relinquished the command to Lieutenant General Sir Gerald Templer, a fellow student during Barker's second year at the Staff College in the late 1920s, in February 1950.