The crisis began over a book of worship. Charles I and his archbishop, William Laud, pursued a programme of beauty in holiness that moved communion tables back to the east end behind rails, restored ceremony, and to many of the king's subjects looked like a road back to Rome. In 1637 the attempt to impose a new prayer book on Scotland produced riots in Edinburgh, the National Covenant of 1638, and two wars the king could not pay for, which forced him to recall the parliament he had ruled without for eleven years.
That parliament put Laud in the Tower, and by 1641 was debating whether to pull episcopacy up root and branch. John Morrill's work on the origins of the fighting argues that religion, more than taxation or constitutional principle, is what moved ordinary people to take up arms in 1642, and that the English Civil War is best understood as the last of Europe's wars of religion rather than the first of its modern revolutions.
Parliament won the argument as well as the war. The Westminster Assembly met from 1643, episcopacy was abolished in 1646, the Book of Common Prayer was replaced in 1645 by a Directory of Public Worship without set prayers, Christmas and the other feasts were suppressed as unscriptural, and on 30 January 1649 the king was tried and beheaded in front of his own banqueting house.