Final answer:
The Act of Supremacy passed in 1534 made Henry VIII the head of the Church of England, marking England's split from the Catholic Church.
Step-by-step explanation:
The document that made Henry VIII head of the Church of England was the 1534 Act of Supremacy, which was passed by Parliament. Prior to this, Henry VIII had been a devout Catholic and a determined opponent of Lutheran reform. However, his desire for a male heir and the Pope's refusal to annul his marriage to Catherine of Aragon led him to break away from the Catholic Church and establish a new national Protestant church, the Church of England. The Act of Supremacy declared the English church no longer bound by the Pope's authority and established the Church of England with the English monarch as its head. Afterwards, Henry was free to annul his own marriage and marry Anne Boleyn, who he hoped would give him a male heir.
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