Archbishop Laud had been the main driving force behind Charles I's attempt to reform the Churches of England and Scotland along Arminian lines, which had angered Puritans as its ideals seemed unnervingly close to those of Roman Catholicism. His attempt to introduce a new Prayer Book in Scotland had sparked the Covenanters movement and the Bishops' Wars. As a result, when the Long Parliament met in November 1640, he was a prime candidate for attack. He was impeached on the grounds of having taken on tyrannical powers, having subverted the true religion, and having caused the Scottish wars. He was imprisoned in the Tower of London, and finally executed on 10th January 1645.