Monarchy of Ireland and Ireland in a personal union. The Union of the Crowns in 1603 expanded the personal union to include Scotland. The personal union between England and Scotland became a political union with the enactments of the Acts of Union 1707, which created the Kingdom of Great Britain. The crowns of Great Britain and Ireland remained in personal union until it was ended by the Acts of Union 1800, which united Ireland and Great Britain into the United Kingdom of Great Britain and Ireland from January 1801 until December 1922. After that date, most of Ireland left the United Kingdom to
Citation of United Kingdom legislation (OS); before that date, legislation was passed either by the Parliament of England or the Parliament of Scotland. Acts passed by each of these parliaments, except for the Parliament of Scotland, are cited in the same way as pre-1963 Acts of the Parliament of the United Kingdom; i.e., by parliamentary session and chapter number. Acts passed by the Parliament of Scotland are cited by calendar year and chapter number. Note also that Acts of the last session of the Parliament of Great Britain and the first session of the Parliament of the United Kingdom are both cited as "41 Geo.