This is a study of the rise of English Arminianism and the growing religious division in the Church of England during the decades before the Civil War of the 1640s. The author argues that it was Arminianism, not the rise of puritanism, that was a major cause of the war, not only because it was embraced by and imposed by an increasingly absolutist Charles I, which heightened the religious and political tensions of the period. Almost all English Protestants were members of the established church. Consequently, what was a theological dispute about rival views of the Christian faith, Arminianism promoting the role of the sacraments and the grace they conferred, Calvinism focusing on the grace of predestination, assumed wider significance as a struggle for control of that church. When Armianism triumphed, Puritan opposition to the established church was rekindled.