The Parliament of England passed the first Act of Supremacy, making King Henry VIII head of the Church of England, supplanting the pope and the Catholic Church.

The Parliament of England was the legislature of the Kingdom of England from the 13th century until 1707 when it was replaced by the Parliament of Great Britain. Parliament evolved from the great council of bishops and peers that advised the English monarch. Great councils were first called Parliaments during the reign of Henry III. By this time, the king required Parliament's consent to levy taxation.

The Acts of Supremacy are two acts passed by the Parliament of England in the 16th century that established the English monarchs as the head of the Church of England; two similar laws were passed by the Parliament of Ireland establishing the English monarchs as the head of the Church of Ireland. The 1534 act declared King Henry VIII and his successors as the Supreme Head of the Church, replacing the Pope. This first act was repealed during the reign of the Catholic Queen Mary I. The 1558 act declared Queen Elizabeth I and her successors the Supreme Governor of the Church, a title that the British monarch still holds.

Henry VIII was King of England from 22 April 1509 until his death in 1547. Henry is known for his six marriages and his efforts to have his first marriage annulled. His disagreement with Pope Clement VII about such an annulment led Henry to initiate the English Reformation, separating the Church of England from papal authority. He appointed himself Supreme Head of the Church of England and dissolved convents and monasteries, for which he was excommunicated by the pope.

The Church of England is the established Christian church in England and the Crown Dependencies. It was the initial church of the Anglican tradition. The Church traces its history to the Christian hierarchy recorded as existing in the Roman province of Britain by the 3rd century and to the 6th-century Gregorian mission to Kent led by Augustine of Canterbury. Its members are called Anglicans.