The title of Supreme Head of the Church of England was created in 1531[1] for King Henry VIII when he first began to separate the Church of England from the authority of the Holy See and allegiance to the papacy, then represented by Pope Clement VII.
Pope Paul III excommunicated Henry in 1538 over his divorce from Catherine of Aragon.
Henry's daughter, Queen Mary I, a staunch Catholic, attempted to restore the English church's allegiance to the Pope and repealed the Act of Supremacy in 1555.
[2] Her half-sister, Elizabeth I, took the throne in 1558 and Parliament passed the Act of Supremacy of 1558 that restored the original act.
[3] The new Oath of Supremacy that nobles were required to swear gave the Queen's title as supreme governor of the church rather than supreme head, to avoid the charge that the monarchy was claiming divinity or usurping Christ, whom the Bible explicitly identifies as Head of the Church.