Well, it's similar to the UK and Ireland. UK and Ireland are both part of the British Isles, and even though Northern Ireland is part of the UK, it is not part of Great Britain, which only refers to Scotland, England, and Wales. The countries that make up the UK each have their own devolved government and legislature but are all subject to the national government and parliament. Jersey, Guernsey, and the Isle of Man are not part of the UK but are crown dependencies that are subject to the British crown... It gets quite complex, that's for certain.