In January 1919, Wilson was promoted to brevet lieutenant colonel and attended the Staff College, Camberley. Between 1920 and 1923, he was a company commander at Sandhurst. He next commanded a battalion of the Rifle Brigade in India. In 1930, Wilson was promoted to colonel and appointed a senior instructor at the Staff College. He then commanded the 6th Rifle Brigade. After being promoted to major general in 1935, Wilson went on half pay until August 1937, when he took command of the 2nd Division at Aldershot.
In June 1939, Wilson was promoted to lieutenant general and assigned to command the British Army of the Nile in Egypt. As such, he oversaw the 1940 campaign of Lieutenant General Richard O'Connor against Marshal Rodolfo Graziani's Italian forces in Egypt and Libya. Following the British victories against the Italians in Libya, Wilson became military governor of Cyrenaica in February 1941. The next month, however, he assumed command of the four-division Allied force sent to Greece. His skill in the delaying action and retreat that ensued did much to reduce losses and allowed the Royal Navy to extricate most of the expeditionary force.
In May 1941, General Archibald Wavell, commander in chief of British forces in the Middle East, appointed Wilson to command British troops in Palestine and Transjordan. With a two-division force, Wilson quelled a pro-German coup in Iraq that same month, and in June, he launched a campaign against Vichy French forces in Syria. In July, he concluded the armistice that gave that Allies control of Syria and Lebanon.
Wilson then commanded the Persia-Iraq Theater and the Ninth Army before succeeding General Harold Alexander in as commander in chief, Middle East, in January 1943, conducting an operation against the Dodecanese Islands. In January 1944, Wilson replaced Eisenhower as commander in chief of the Mediterranean Theater and thus had overall responsibility for Allied operations in Italy. He also helped plan the landing at Anzio and Operation dragoon, the Allied landing in southern France. After the death of General Sir John Dill in November, Wilson was promoted to field marshal in January and dispatched to Washington as head of the British Joint Staff Mission. In this capacity, he attended the final wartime conferences at Yalta and Potsdam. Elevated to the peerage in 1946 as First Baron Wilson of Libya and Stowlangtoft, Wilson retired from the army in April 1947 and wrote his memoirs. He was constable of the Tower of London between 1955 and 1960. He died in the Chilterns (Aylesbury), England, on 31 December 1964.
Britton W. MacDonald and Spencer C. Tucker
Dewar, Michael. "Wilson." In John Keegan, ed., Churchill's Generals, 166–182. New York: Grove Weidenfeld, 1991.; Wilson, Henry M. Eight Years Overseas, 1939–1947. New York: Hutchinson, 1949.