The Act of Settlement is an Act of the Parliament of England that settled the succession to the English and Irish crowns to only Protestants, which passed in 1701. More specifically, anyone who became a Roman Catholic, or who married one, became disqualified to inherit the throne. This had the effect of deposing the remaining descendants of Charles I, other than his Protestant granddaughter Anne, as the next Protestant in line to the throne was Sophia of Hanover. Born into the House of Wittelsbach, she was a granddaughter of James VI and I from his most junior surviving line, with the crowns descending only to her non-Catholic heirs. Sophia died shortly before the death of Queen Anne, and Sophia's son succeeded to the throne as King George I, starting the Hanoverian dynasty in Britain.
The Act of Supremacy 1558 had confirmed the independence of the Church of England from Roman Catholicism under the English monarch. One of the principal factors which contributed to the Glorious Revolution was the perceived assaults made on the Church by King James II, a Roman Catholic, who was deposed in favour of his Protestant daughter Mary II and her husband William III. The need for this Act of Settlement was prompted by the inability of William and Mary, as well as of Mary's Protestant sister (the future Queen Anne), to produce any surviving children, and by the perceived threat posed by the pretensions to the throne by remaining Roman Catholic members of the House of Stuart.
The Act played a key role in the formation of the Kingdom of Great Britain as, though England and Scotland had shared a monarch since 1603, they had remained separately governed countries, with the Act catalysing the Union of England and Scotland. However, the Parliament of Scotland was more reluctant to abandon the House of Stuart, members of which had been Scottish monarchs long before they became English. Moreover, the Act also placed limits on both the role of foreigners in the British government and the power of the monarch with respect to the Parliament of England, though some of those provisions have been altered by subsequent legislation.
Along with the Bill of Rights 1689, the Act of Settlement remains today one of the main constitutional laws governing the succession not only to the throne of the United Kingdom, but to those of the other Commonwealth realms, whether by assumption or by patriation. The Act of Settlement cannot be altered in any realm except by that realm's own parliament and, by convention, only with the consent of all the other realms, as it touches on the succession to the shared crown. On 26 March 2015, following the Perth Agreement, legislation amending the Act came into effect across the Commonwealth realms that removed the disqualification arising from marriage to a Roman Catholic and instituted absolute primogeniture.
Background
Following the Glorious Revolution, the line of succession to the English throne was governed by the Bill of Rights 1689, which declared that the flight of James II from England to France during the revolution amounted to an abdication of the throne and that James's daughter Mary II and her husband/cousin, William III (William of Orange, who was also James's nephew), were James's successors. The Bill of Rights also provided that the line of succession would go through Mary's Protestant descendants by William and any possible future husband should she outlive him, then through Mary's sister Anne and her Protestant descendants, and then to the Protestant descendants of William III by a possible later marriage should he outlive Mary. During the debate, the House of Lords had attempted to append Sophia and her descendants to the line of succession, but the amendment failed in the Commons.
Mary II died childless in 1694, after which William III did not remarry. In 1700, Prince William, Duke of Gloucester, who was Anne's only child to survive infancy, died of what may have been smallpox at the age of 11. Thus, Anne was left as the only person in line to the throne. The Bill of Rights excluded Catholics from the throne, which ruled out James II and his children (as well as their descendants) sired after he converted to Catholicism in 1668. However, it did not provide for the further succession after Anne. Parliament thus saw the need to settle the succession on Sophia and her descendants, and thereby guarantee the continuity of the Crown in the Protestant line.
With religion and lineage initially decided, the ascendancy of William of Orange in 1689 would also bring his partiality to his foreign favourites that followed. By 1701 English jealousy of foreigners was rampant, and action was considered necessary.
