Charles struggled for power with the Parliament of England. He firmly believed in the [[Divine Right of Kings]], and many in [[England]] feared that he was attempting to gain absolute power.
Religious conflicts were a notable feature of Charles' reign. He married a Catholic princess, Henrietta Maria of France, over the objections of Parliament and public opinion. Many of Charles' subjects felt that he brought the Church of England too close to Roman Catholicism, despite the fact that Charles was himself committed to Anglicanism. Charles' later attempts to force religious reforms upon Scotland , including a new Book of Prayer led to the Bishops' Wars that weakened England's government and led to his downfall.
His last years were marked by the English Civil War, in which he was opposed by the forces of Parliament and by Puritans, who were hostile to his religious policies and alleged Catholic sympathy. Charles was defeated in the first Civil War (1642 - 1645), after which Parliament expected him to accept demands for a constitutional monarchy. He instead remained defiant by attempting to forge an alliance with Scotland and escaping to the Isle of Man. This provoked a second Civil War (1648 - 1649) and a second defeat for Charles, who was tried and then executed for high treason. The monarchy was then abolished and a republic called the Commonwealth of England was declared. Charles's son, Charles II, became King after the restoration of the monarchy in 1660.
King Charles I was canonized by the [[Anglican Communion]] as Saint King Charles, the Martyr, his Feast Day is 30 January.