George VI (reigned 1936-52), a conscientious and dedicated man, worked hard to adapt to the role into which he was suddenly thrown. In 1923 he had married Lady Elizabeth Bowes-Lyon; and he carried out many official engagements at home and abroad, and established The Duke of York's Summer Camps for boys from all backgrounds. Reserved by nature, and of deep religious belief, he did not expect to become King.
The King paid a State Visit to France in 1938, and to Canada and the United States in 1939 (he was the first British monarch to enter the United States). His dedication to duty, particularly during the Second World War, when he remained for most of the time at Buckingham Palace (the Palace was bombed nine times during the war), and when he and his wife visited severely bombed areas in the East End of London and elsewhere in the country, gained him great popularity. The King developed a close working relationship with his wartime Prime Minister, Winston Churchill, as most of Europe fell to Nazi Germany.

Recognising the total nature of modern warfare, in 1940 the King instituted the George Cross and George Medal, to be awarded for acts of bravery by citizens. In 1942, the George Cross was awarded to the island and people of Malta in recognition of the heroism with which they had resisted the enemy siege.

Having served in the Navy during the First World War, including the Battle of Jutland, the King was anxious to visit his troops whenever possible. He went to France in 1939 to inspect the British Expeditionary Force, and to North Africa in 1943 after the victory of El Alamein. In June 1944, the King visited his Army on the Normandy beaches 10 days after D-Day, and later that year he visited troops in Italy and the Low Countries.

On VE (Victory in Europe) Day, 8 May 1945, Buckingham Palace was a focal point of the celebrations. The war had immeasurably strengthened the link between the King and his people.

In 1947, the King undertook a major tour of South Africa, accompanied by the Queen and their daughters, Princess Elizabeth and Princess Margaret - the first time a sovereign had undertaken a tour with his family. When India and Pakistan became independent in 1947, George ceased to be Emperor of India. Changes in the Commonwealth meant that its tie was no longer based on common allegiance to the Crown, but upon recognition of the Sovereign as Head of the Commonwealth. These changes in the Commonwealth relationship and the social reforms of the post-war Labour government occurred against the background of Britain's weak post-war economic position and the beginning of the Cold War, which meant that the privations of war were extended well into the post-war period.

By 1948, it seemed that Britain had overcome the worst hardships of the post-war years, but the strain of the Second World War and the tensions of the post-war period had taken their toll on the King's health. The King failed to recover from a lung operation, and died in his sleep on 6 February 1952 at Sandringham; he was aged 56. After lying in state at Westminster Hall, the King's funeral was held at St George's Chapel, Windsor, where he lies buried. At the King's funeral, attached to the Government's wreath was a card on which Churchill had written the phrase inscribed on the Victoria Cross - 'For Valour'.