World War II: Gunners of the Ceylon Garrison Artillery on Horsburgh Island in the Cocos Islands rebel in the Cocos Islands Mutiny. Their mutiny is crushed and three of them are executed, the only British Commonwealth soldiers to be executed for mutiny during the Second World War.

The Cocos (Keeling) Islands, officially the Territory of Cocos (Keeling) Islands, are an Australian external territory in the Indian Ocean, comprising a small archipelago approximately midway between Australia and Sri Lanka and relatively close to the Indonesian island of Sumatra. The territory's dual name reflects that the islands have historically been known as either the Cocos Islands or the Keeling Islands.

The Cocos Islands mutiny was a failed mutiny by Sri Lankan soldiers against British officers, on the Cocos (Keeling) Islands on 8 May 1942, during the Second World War.

The Commonwealth of Nations, often referred to as the British Commonwealth or simply the Commonwealth, is an international association of 56 member states, the vast majority of which are former territories of the British Empire from which it developed. They are connected through their use of the English language and cultural and historical ties. The chief institutions of the association are the Commonwealth Secretariat, which focuses on intergovernmental relations, and the Commonwealth Foundation, which focuses on non-governmental relations between member nations. Numerous organisations are associated with and operate within the Commonwealth.