A Commonwealth realm is a sovereign state that has Charles III as its monarch and ceremonial head of state. All the realms are equal with and independent of the others, though one person, resident in the United Kingdom, acts as monarch of each. The phrase Commonwealth realm is an informal description not used in any law.
High Commissioner of Belize to the UK meets with the British Minister of State for Foreign and Commonwealth Affairs. High Commissioners act as liaisons between the governments of the Commonwealth realms.
Prince George, second in the line of succession
King George VI, with Queen Elizabeth, grants royal assent to bills in the Senate of Canada, May 1939
Antigua and Barbuda is a sovereign island country in the Caribbean. It lies at the conjuncture of the Caribbean Sea and the Atlantic Ocean in the Leeward Islands part of the Lesser Antilles.
Antigua in 1823
The Queen on 1953 Antiguan stamps