Constitution of the United Kingdom from the state, which was confirmed by the Church of Scotland Act 1921. England and Wales share the same legal system, while Scotland and Northern Ireland each have their own distinct systems. These distinctions arose prior to and were retained after the unions according to the terms of the 1706 Treaty of Union, ratified by the 1707 Acts of Union, and the Acts of Union 1800. Reforms since 1997 have decentralised the UK by setting up a devolved Scottish Parliament and assemblies in Wales and Northern Ireland. The UK was formed as a unitary state, though Scotland and England retained
Acts of Union 1707 the 1639-1651 Wars of the Three Kingdoms. The 1639–1640 Bishops' Wars confirmed the primacy of the Presbyterian Church of Scotland or kirk and established a Covenanter government in Scotland. The Scots remained neutral when the First English Civil War began in 1642, but grew concerned as to the impact of Royalist victory on Scotland after Parliamentary defeats in the first year of the war. Religious union with England was also seen as the best way to preserve a Presbyterian kirk. The 1643 Solemn League and Covenant provided Scottish military support for the English Parliament in return for a religious union