Short term causes: Charles had a very different personality compared to James. Charles was arrogant, conceited and a strong believer in the divine rights of kings. He had witnessed the damaged relationship between his father and Parliament, and considered that Parliament was entirely at fault.
Religion was a major cause of the English Civil War. It was part of a Europe wide conflict between Roman Catholicism and Protestantism. At the start of his reign (1625) King Charles I had married the Roman Catholic Henrietta Maria of France.
The English Civil Wars (1642-1651) stemmed from conflict between Charles I and Parliament over an Irish insurrection. The first war was settled with Oliver Cromwell's victory for Parliamentary forces at the 1645 Battle of Naseby.