Second World War: The Royal Air Force's "Dambusters" squadron embarked on an attack on German dams using bouncing bombs designed by Barnes Wallis.

World War II or the Second World War was a global conflict between two coalitions: the Allies and the Axis powers. Nearly all of the world's countries participated, with many nations mobilising all resources in pursuit of total war. Tanks and aircraft played major roles, enabling the strategic bombing of cities and delivery of the first and only nuclear weapons ever used in war. World War II is the deadliest conflict in history, causing the death of 70 to 85 million people, more than half of whom were civilians. Millions died in genocides, including the Holocaust, and by massacres, starvation, and disease. After the Allied victory, Germany, Austria, Japan, and Korea were occupied, and German and Japanese leaders were tried for war crimes.

The Royal Air Force (RAF) is the air and space force of the United Kingdom, British Overseas Territories and Crown Dependencies. It was formed towards the end of the First World War on 1 April 1918, on the merger of the Royal Flying Corps (RFC) and the Royal Naval Air Service (RNAS). Following the Allied victory over the Central Powers in 1918, the RAF emerged as the largest air force in the world at the time. Since its formation, the RAF has played a significant role in British military history. In particular, during the Second World War, the RAF established air superiority over Nazi Germany's Luftwaffe during the Battle of Britain, and led the Allied strategic bombing effort.

Number 617 Squadron is a Royal Air Force aircraft squadron commonly known as The Dambusters for its actions during Operation Chastise against German dams during the Second World War, originally based at RAF Scampton in Lincolnshire and currently based at RAF Marham in Norfolk. In the early 21st century it operated the Panavia Tornado GR4 in the ground attack and reconnaissance role until being disbanded on 28 March 2014. The Dambusters reformed on 18 April 2018, and was equipped at RAF Marham in June 2018 with the Lockheed Martin F-35B Lightning, becoming the first squadron to be based in the UK with this advanced STOVL type. The unit is composed of both RAF and Royal Navy personnel, and operates from the Royal Navy's Queen Elizabeth-class aircraft carriers.