Bradley was placed in charge of the 1st US Army in 1944 and after arriving in Britain helped to plan Operation Overlord. After the D-Day landings Bradley was appointed commander of the 12th Army Group. Promoted to four-star general on 12th March 1945, he succeeded Dwight D. Eisenhower as army chief of staff in 1948. The following year he became chairman of the Joint Chiefs of Staff. His memoirs, A Soldier's Story, was published in 1951.