Unionism in England possession) and Scotland was created by the Acts of Union, passed in the parliaments of both kingdoms in 1707 and 1706 respectively, which united the governments of what had previously been independent states (though they had shared the same monarch in a personal union since 1603) under the Parliament of Great Britain. The Union was brought into existence under the Acts of Union on 1 May 1707. With the Act of Union 1800, the Kingdom of Ireland united with Great Britain into what then formed the United Kingdom of Great Britain and Ireland. The history of the Unions is reflected
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.