The history of the Royal Air Force, the air force of the United Kingdom, spans a century of British military aviation.
The RAF was founded on 1 April 1918, towards the end of the First World War by merging the Royal Flying Corps and the Royal Naval Air Service. After the war, the RAF was greatly reduced in size and during the inter-war years was used for policing operations in the British Empire. The RAF underwent rapid expansion prior to and during the Second World War. During the war it was responsible for the aerial defence of Great Britain, the strategic bombing campaign against Germany and tactical support to the British Army around the world.
During the Cold War, the main role of the RAF was the defence of the continent of Europe against potential attack by the Soviet Union, including holding the British nuclear deterrent for a number of years. After the end of the Cold War, the RAF took part in several large scale operations, including the Gulf War, the Kosovo War, the War in Afghanistan, and the Iraq War.