George VI's public life began in naval service during the First World War and continued through royal duties as Duke of York. Visits to industrial communities and youth welfare initiatives helped establish a role distinct from that of the heir to the throne. Work with speech therapist Lionel Logue enabled him to manage a stammer that complicated public speaking. Marriage to Elizabeth Bowes-Lyon in 1923 created a close family partnership. Edward VIII's abdication in December 1936 unexpectedly made him king, requiring adaptation to a constitutional office for which his elder brother had long been prepared.

George worked to restore confidence in the monarchy after the abdication crisis. State visits, including travel to Canada and the United States in 1939, strengthened international relationships and demonstrated the changing position of the dominions. He remained dependent on ministerial advice in government and foreign affairs; his importance lay in representation, continuity and the exercise of constitutional responsibilities. Overcoming his speech difficulties was only one element of his royal duties.

During the Second World War the king and queen visited bombed communities, factories, hospitals and service personnel. Remaining associated with London during the Blitz made them symbols of shared danger, although their movements also included necessary protection and travel. Broadcasts connected the crown with wartime sacrifice and determination. George established the George Cross in 1940 to recognize exceptional gallantry, especially among civilians. His relationship with Churchill developed into regular consultation, but military operations and policy remained the responsibility of the government and armed forces rather than the sovereign.

The postwar years brought Labour's social reforms, austerity and the dismantling of major imperial structures. Indian and Pakistani independence in 1947 ended his position as emperor of India, while the Commonwealth developed a form able to include republics as well as realms. The London Declaration of 1949 recognized him as head of that association, separating the symbolic role from allegiance to him as monarch. Declining health curtailed travel and official activity. He died at Sandringham in February 1952, and Elizabeth II succeeded him. His reign gave the monarchy continuity during war and major constitutional change, while illustrating how royal public influence could coexist with limited direct political power.