Union of the Crowns create a new "imperial" throne of "Great Britain". England and Scotland continued as autonomous states sharing a monarch with Ireland (with an interregnum in the 1650s during the republican unitary state of the Commonwealth and the Protectorate), until the Acts of Union of 1707 during the reign of the last Stuart monarch, Anne. In August 1503, James IV of Scotland married Margaret, eldest daughter of Henry VII of England, and the spirit of the new age was celebrated by the poet William Dunbar in "The Thrissil and the Rois". The marriage was the outcome of the Treaty of Perpetual Peace,
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