According to the Official Website of the British Monarchy (and who should know better) , “A Commonwealth Realm is a country which has the Queen as its Monarch. There are 15 Commonwealth Realms in addition to the UK: Australia, New Zealand, Canada, Jamaica, Antigua and Barbuda, Belize, Papua New Guinea, St. Christopher and Nevis, St. Vincent and the Grenadines, Tuvalu, Barbados, Grenada, Solomon Islands, St. Lucia and The Bahamas.
Blue: Current Commonwealth Realms, Red: no longer Commonwealth Realms. Wikimedia Commons
Sounds like a wonderful list of places to pop by and visit if you get tired of the British Isles.