The Roman Catholic Relief Act 1829, passed by Parliament in 1829, was the culmination of the process of Catholic Emancipation throughout the United Kingdom. In Ireland it repealed the Test Act 1672 and the remaining Penal Laws which had been in force since the passing of the Disenfranchising Act of the Irish Parliament of 1728. Its passage followed a vigorous campaign that threatened insurrection led by Irish lawyer Daniel O'Connell. The British leaders, starting with the Prime Minister the Duke of Wellington and his top aide Robert Peel, although personally opposed, gave in to avoid civil strife. Ireland was quiet after the passage.
The act permitted members of the Catholic Church to sit in the parliament at Westminster. O'Connell had won a seat in a by-election for Clare in 1828 against an Anglican. Under the then extant penal law, O'Connell as a Catholic, was forbidden to take his seat in Parliament. Peel, the Home Secretary, until then was called "Orange Peel" because he always supported the Orange (anti-Catholic) position. Peel now concluded: "though emancipation was a great danger, civil strife was a greater danger." Fearing a revolution in Ireland, Peel drew up the Catholic Relief Bill and guided it through the House of Commons. To overcome the vehement opposition of both the House of Lords and King George IV, the Duke of Wellington worked tirelessly to ensure passage in the House of Lords, and threatened to resign as Prime Minister if the King did not give Royal Assent.
The campaign for Catholic emancipation in Ireland, 1828–1829, was led by Daniel O'Connell (1775–1847), organiser of the Catholic Association, but many others were active as well, both for and against.
As Lord Lieutenant of Ireland from 1822 to 1828, the Marquess Wellesley (brother of the Duke of Wellington) played a critical role in setting the stage for the Catholic Emancipation Bill. His policy was one of reconciliation that sought to have the civil rights of Catholics restored while preserving those rights and considerations important to Protestants. He used force in securing law and order when riots threatened the peace, and he discouraged the public agitation of both the Protestant Orange Order and the Catholic Society of Ribbonmen.
Bishop John Milner was an English Catholic cleric and writer highly active in promoting Catholic emancipation until his death in 1826. He was a leader in anti-Enlightenment thought and had a significant influence in England as well as Ireland, and was involved in shaping the Catholic response to earlier efforts in Parliament to enact Catholic emancipation measures.
Meanwhile, Ulster Protestants mobilised, after a delayed start, to stop emancipation. By late 1828, Protestants of all classes began to organise after the arrival of O'Connellite Jack Lawless who planned a series of pro-emancipation meetings and activities across Ulster. His move galvanised the Protestants to form clubs, distribute pamphlets and set up petition drives. However the Protestant protests were not well funded or coordinated and lacked critical support from the British government. After Catholic relief had been granted, the Protestant opposition divided along class lines. The aristocracy and gentry became quiescent while the middle and working classes showed dominance over Ulster's Catholics through Orange parades.
The Parliamentary Elections (Ireland) Act 1829 (10 Geo. IV, c. 8) which accompanied emancipation and received its Royal Assent on the same day, was the only major ‘security’ eventually required for it. This Act disenfranchised the minor landholders of Ireland, the so-called Forty Shilling Freeholders and raised fivefold the economic qualifications for voting. Starting in the initial relief granting the vote by the Irish Parliament in 1793, any man renting or owning land worth at least forty shillings (two pounds sterling), had been permitted to vote. Under the Act, this was raised to ten pounds.
The act also forbade the use of the episcopal titles already used by the Church of England (10 Geo. IV, c. 7, s. 24). It imposed a penalty of £100 on 'any person, not authorised by law, who should assume the title of any archbishop, bishop or dean' and extended the provisions to the 'assumption of ecclesiastical titles derived from any city, town, or place in England and Ireland, not being in an existing see'. This was reinforced with the Ecclesiastical Titles Act 1851, which threatened confiscation of property of anyone outside the "united Church of England and Ireland" to use any episcopal title "of any city, town or place, or of any territory or district (under any designation or description whatsoever), in the United Kingdom". The 1851 act was never enforced and was repealed in 1871. The other impositions in the act, such as admittance to Catholic religious orders and public processions being illegal, were repealed with the Roman Catholic Relief Act of 1926.
J. C. D. Clark (1985) depicts England before 1828 as a nation in which the vast majority of the people believed in the divine right of kings, and the legitimacy of a hereditary nobility, and in the rights and privileges of the Anglican Church. In Clark's interpretation, the system remained virtually intact until it suddenly collapsed in 1828, because Catholic emancipation undermined its central symbolic prop, the Anglican supremacy. Clark argues that the consequences were enormous: "The shattering of a whole social order....What was lost at that point... was not merely a constitutional arrangement, but the intellectual ascendancy of a worldview, the cultural hegemony of the old elite." Clark's interpretation has been widely debated in the scholarly literature, and almost every historian who has examined the issue has highlighted the substantial amount of continuity between the periods before and after 1828–1832.
Eric J. Evans (1996) emphasises that the political importance of emancipation was that it split the anti-reformers beyond repair and diminished their ability to block future reform laws, especially the great Reform Act of 1832. Paradoxically, Wellington's success in forcing through emancipation converted many Ultra-Tories to demand reform of Parliament. They saw that the votes of the rotten boroughs had given the government its majority. Therefore, it was an ultra-Tory, the Marquess of Blandford, who in February 1830 introduced the first major reform bill, calling for the transfer of rotten borough seats to the counties and large towns, the disfranchisement of non-resident voters, the preventing of Crown office-holders from sitting in Parliament, the payment of a salary to MPs, and the general franchise for men who owned property. The ultras believed that a widely based electorate could be relied upon to rally around anti-Catholicism.