Political association of mostly former British Empire territories
Source (Wikipedia): Commonwealth of Nations

The Commonwealth of Nations, often simply referred to as 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 historical-cultural ties. The chief institutions of the organisation 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.