FIFA allows England, Northern Ireland, Scotland and Wales to field independent teams due to historical reasons and that they control the laws of the game. During the rise of association football in Great Britain each country created their own governing body for association football. The Football Association (England), The Scottish Football Association, Football Association of Wales, Irish Football Association also known as the Home Nations.

Each governing body had slightly different rules and in 1882 they met to agree on rules for international tournaments. Also from this meeting was the formation of the British Home Championship, which they receive their name from. In 1886 the four associations held the first meeting of the International Football Association Board, to govern the laws of association football. The IFAB gave each association an equal vote on changing the laws of the game. When FIFA was founded in 1904, FIFA decided they would enforce the laws of the game according to IFAB. Over the years FIFA has become part of the IFAB but due to the voting structure FIFA can not change any law of the game without the approval of most of the Home Nations.

Currently the reason why there is a Great Britain is since 1995 the Olympic Charter has not allowed for the recognition of non-sovereign nations—section 31.1 of the Olympic Charter states that to be considered a country a nation must be "an independent State recognized by the international community". This blocks the four Home Nations from creating their own Olympic committees. Historically outside of football codes United Kingdom has used athletes from each Home Nation.

Edit: Fixed a typo