Plaid Cymru

Ideology

Plaid Cymru is a centre-left to left-wing party that heavily emphasises its Welsh character, having been described as regionalist, civic nationalist, left-wing nationalist, Welsh nationalist, and pro-independence.

Economically, the party gradually adopted a socialist line and welcomed many socialists since its founding, but formalised its goal of "decentralized socialism" only in 1981. The party has been described as democratic socialist and left-wing, and later as social democratic and centre-left, but in recent years the former party leader Leanne Wood has described herself as a socialist and the party has gradually been re-conceived as left-wing and also left-wing populist.

The party has been described as environmentalist, and opposes new nuclear power plants and nuclear weapons (including the UK's Trident nuclear weapons programme).

In May 2025, the party's leader, Rhun ap Iorwerth, stated there was no plan for an independence referendum in the first term of a Plaid Cymru government if they are elected at the 2026 Senedd election, and that talk of a referendum would not take place before 2030. However, the party continues to hold an official position favouring Welsh independence. At the party's October 2025 conference, the party's members backed a motion to establish a "standing commission" to develop a white paper on Welsh independence. However, leader Rhun ap Iorwerth has stated that the white paper would not be for Plaid's first term of government if they were elected, although the commission may still collect evidence for the white paper during a Plaid first term. A date was not given but it is suggested they may develop plans if Plaid win both the 2026 and 2030 Senedd elections. Ap Iorweth stated they aim to "kick start the national debate on independence", "take the discussion forward" and "call the referendum when the time is right", with members backing a statement that Wales was "on a journey to independence".

History

Beginnings

While both the Labour and Liberal parties of the early 20th century had accommodated demands for Welsh home rule, no political party existed for the purpose of establishing a Welsh government. Plaid Genedlaethol Cymru (Welsh for 'the National Party of Wales') was formed on 5 August 1925, by Moses Gruffydd, H. R. Jones and Lewis Valentine, members of Byddin Ymreolwyr Cymru (Welsh for 'the Home Rule Army of Wales'; lit. 'the Self-Rulers' Army of Wales'); and Fred Jones, Saunders Lewis of Y Mudiad Cymreig (Welsh for 'the Welsh Movement') and D. Edmund Williams. Initially, home rule for Wales was not an explicit aim of the new movement; keeping Wales Welsh-speaking took primacy, with the aim of making Welsh the only official language of Wales.

Plaid Genedlaethol Cymru's principles (translated from Welsh), as of 1925, were as followed:

"(to) Have a Welsh Wales, That includes;", "To preserve the Welsh language as the only living language of Wales, and to restore it as the official language in public life and administration throughout Wales", "To secure for the Welsh language a central place in the educational system of Wales, from elementary school to university", they outlined that they wanted Wales to be "a self-governing nation" and they would do so by having "Control over Welsh affairs through a national parliament elected by the people", "Representation in the League of Nations and the right to determine its own relationships as a member nation among the nations of the world", "Freedom from English political domination", have "Control over all local resources within Wales".

In the 1929 general election, the party contested its first parliamentary constituency, Caernarvonshire, polling 609 votes, or 1.6% of the vote for that seat. The party contested few such elections in its early years, partly due to its ambivalence towards Westminster politics. Indeed, the candidate Lewis Valentine, the party's first president, offered himself in Caernarvonshire on a platform of demonstrating Welsh people's rejection of English dominion.

1930s

By 1932, the aims of self-government and Welsh representation at the League of Nations had been added to that of preserving Welsh language and culture. However, this move, and the party's early attempts to develop an economic critique, did not broaden its appeal beyond that of an intellectual and socially conservative Welsh language pressure group. The alleged sympathy of the party's leading members (including President Saunders Lewis) towards Europe's totalitarian regimes compromised its early appeal further.

Saunders Lewis, David John Williams and Lewis Valentine set fire to the newly constructed RAF Penyberth air base on the Llŷn Peninsula in Gwynedd in 1936, in protest at its siting in the Welsh-speaking heartland. The leaders' treatment, including the trial judge's dismissal of the use of Welsh and their subsequent imprisonment in Wormwood Scrubs, led to "The Three" becoming a cause célèbre. This heightened the profile of the party dramatically and its membership had doubled to nearly 2,000 by 1939.

1940s

Penyberth, and Plaid Cymru's neutral stance during the Second World War, prompted concerns within the UK Government that it might be used by Germany to insert spies or carry out other covert operations. In fact, the party adopted a neutral standpoint and urged (with only limited success) conscientious objection to war service.

In 1943, Saunders Lewis contested the University of Wales parliamentary seat at a by-election, gaining 1,330 votes, or 22%. In the 1945 general election, with party membership at around 2,500, Plaid Cymru contested seven seats, as many as it had in the preceding 20 years, including constituencies in south Wales for the first time. At this time Gwynfor Evans was elected president.

1950s

Gwynfor Evans's presidency coincided with the maturation of Plaid Cymru (as it now began to refer to itself) into a more recognisable political party. Its share of the vote increased from 0.7% in the 1951 general election to 3.1% in 1955 and 5.2% in 1959. In the 1959 election, the party contested a majority of Welsh seats for the first time. Proposals to flood the village of Capel Celyn in the Tryweryn valley in Gwynedd in 1957 to supply the city of Liverpool with water played a part in Plaid Cymru's growth. The fact that the parliamentary bill authorising the dam went through without support from any Welsh MPs showed that the MPs' votes in Westminster were not enough to prevent such bills from passing.

1960s

Support for the party declined slightly in the early 1960s, particularly as support for the Liberal Party began to stabilise from its long-term decline. In 1962, Saunders Lewis gave a radio talk entitled Tynged yr Iaith ('the fate of the language') in which he predicted the extinction of the Welsh language unless action was taken. This led to the formation of Cymdeithas yr Iaith Gymraeg ('the Welsh Language Society') the same year.

Labour's return to power in 1964 and the creation of the post of Secretary of State for Wales appeared to represent a continuation of the incremental evolution of a distinctive Welsh polity, following the Conservative government's appointment of a Minister of Welsh Affairs in 1951 and the establishment of Cardiff as Wales's capital in 1955.

However, in 1966, less than four months after coming in third in the constituency of Carmarthen, Gwynfor Evans captured the seat from Labour at a by-election. This was followed by two further by-elections in Rhondda West in 1967 and Caerphilly in 1968 in which the party achieved massive swings of 30% and 40% respectively, coming within a whisker of victory. The results were caused partly by an anti-Labour backlash. Expectations in coal mining communities that the Wilson government would halt the long-term decline in their industry had been dashed by a significant downward revision of coal production estimates. However, particularly in Carmarthen, Plaid also successfully depicted Labour's policies as a threat to the viability of small Welsh communities.

1970s

In the 1970 general election, Plaid Cymru contested every seat in Wales for the first time and its vote share surged from 4.5% in 1966 to 11.5%. Gwynfor Evans lost Carmarthen to Labour, but regained the seat in October 1974, by which time the party had gained a further two MPs, representing the constituencies of Caernarfon and Merionethshire.

Plaid Cymru's emergence (along with the Scottish National Party) prompted the Wilson government to establish the Kilbrandon Commission on the constitution. The subsequent proposals for a Welsh Assembly were, however, heavily defeated in a referendum in 1979. Despite Plaid Cymru's ambivalence toward home rule (as opposed to outright independence) the referendum result led many in the party to question its direction.

Plaid campaigned to leave the Common Market in the 1975 referendum, feeling that the EC's regional aid policies would "reconcile places like Wales to their subordinate position". Nevertheless, 65% of Welsh voters voted to remain in the EC during a 1975 referendum. The EC was incorporated into the European Union (EU) in 1993.

At the 1979 general election, the party's vote share declined from 10.8% to 8.1% and Carmarthen was again lost to Labour, although Caernarfon and Merionethshire were held by the party.

1980s

Caernarfon MP Dafydd Wigley succeeded Gwynfor Evans as president in 1981, inheriting a party whose morale was at an all-time low. In 1981 the party adopted a policy of "community socialism". While the party embarked on a wide-ranging review of its priorities and goals, Gwynfor Evans fought a successful campaign (including the threat of a hunger strike) to oblige the Conservative government to fulfill its promise to establish S4C, a Welsh-language television station. In 1984, Dafydd Elis-Thomas was elected president, defeating Dafydd Iwan, a move that saw the party shift to the left. Ieuan Wyn Jones (later Plaid Cymru leader) captured Ynys Môn from the Conservatives in 1987. In 1989 Dafydd Wigley once again assumed the presidency of the party.

In 1986, the party established Undeb Credyd Plaid Cymru Credit Union Limited, a savings and loans co-operative based in Roath, Cardiff, open to party members. The credit union closed in the late 2010s and was deregistered in 2023.

1990s

In the 1992 general election, the party added a fourth MP, Cynog Dafis, when he gained Ceredigion and Pembroke North from the Liberal Democrats. Dafis was endorsed by the local branch of the Green Party. The party's vote share recovered to 9.9% at the 1997 general election.

In 1997, following the election of a Labour government committed to devolution for Wales, a further referendum was narrowly won, establishing the National Assembly for Wales. Plaid Cymru became the main opposition to the ruling Labour Party, with 17 seats to Labour's 28. In doing so, it appeared to have broken out of its rural Welsh-speaking heartland, and gained seats in traditionally strong Labour areas in industrial South Wales.

Ahead of the 1999 National Assembly for Wales election, Plaid Cymru dropped its policy of Welsh independence in favour of continued membership in the European Union. These changes in policy were made as it was believed that the electorate in Wales did not view independence as an important issue. It also adopted social democracy for its economic policy in an attempt to weaken Labour. These changes in policy have been used to explain the party's subsequent electoral success in Labour's traditional South East Wales heartlands.

Assembly/Senedd era

In the 1999 election, Plaid Cymru gained seats in traditional Labour areas such as Rhondda, Islwyn and Llanelli, achieving by far its highest share of the vote in any Wales-wide election until the 2026 Senedd election While Plaid Cymru regarded itself as the natural beneficiary of devolution, others attributed its performance in large part to the travails of the Labour Party, whose nomination for Assembly First Secretary, Ron Davies, was forced to stand down in an alleged sex scandal. The ensuing leadership battle, won by Alun Michael, did much to damage Labour, and thus aided Plaid Cymru, whose leader was the more popular and higher profile Dafydd Wigley. The Labour Party's UK national leadership was seen to interfere in the contest and deny the popular Rhodri Morgan victory. Less than two months later, in elections to the European parliament, Labour support slumped further, and Plaid Cymru came within 2.5% of achieving the largest share of the vote in Wales. Under the new system of proportional representation, the party also gained two MEPs.

Plaid Cymru then developed political problems of its own. Dafydd Wigley resigned, citing health problems but amid rumours of a plot against him. His successor, Ieuan Wyn Jones, struggled to impose his authority, particularly over controversial remarks made by a councillor, Seimon Glyn. At the same time, Labour leader and First Minister Alun Michael was replaced by Rhodri Morgan.

In the 2001 general election, notwithstanding Plaid Cymru recording its highest-ever vote share in a general election, 14.3%, the party lost Wyn Jones's former seat of Ynys Môn to Albert Owen, although it gained Carmarthen East and Dinefwr, where Adam Price was elected.

The Assembly elections of May 2003 saw the party's representation drop from 17 to 12, with the seats gained in the 1999 election falling again to Labour and the party's share of the vote declining to 21%. Plaid Cymru narrowly remained the second-largest party in the National Assembly ahead of the Conservatives, Liberal Democrats and a single independent.

On 15 September 2003, folk-singer and county councillor Dafydd Iwan was elected as Plaid Cymru's president. Ieuan Wyn Jones, who had resigned from his dual role as president and Assembly group leader following the losses in the 2003 Assembly election, was re-elected in the latter role. Elfyn Llwyd remained the Plaid Cymru leader in the Westminster Parliament. Under Iwan's presidency, the party formally adopted a policy of independence for Wales within Europe at its conference in September 2003. Plaid Cymru had historically supported Welsh independence but dropped this policy ahead of the 1999 devolved election.

Party leadership

Leaders

The party leader was referred to in English as the president until March 2000, when the separate role of Leader was created.

Elected representatives

Local councillors

198 councillors in local government. They form the Plaid Cymru Councillors Association.

Plaid Cymru is involved in the administration of 7 out of 22 Welsh councils.

Appointments

Election results

House of Commons

*Six seats (Blaenau Gwent, Ceredigion & Pembroke North, Islwyn, Monmouth, Newport West and Torfaen) contested on a joint Plaid Cymru/Green Party ticket

Senedd

The 2026 election used a different voting system with full party-list proportional representation in 16 six-member constituencies.

Local councils

*The 2012 figures exclude Anglesey, where the vote was delayed until 2013. The changes in seats and votes shown for 2012 are a direct comparison since the 2008 elections in the 21 councils up for election (i.e. excluding Anglesey).

In 2008, Plaid won 205 seats including six in Anglesey. For the purposes of this table the 205 figure has been reduced to 199 for the 2012 elections where the party lost 41 of the 199 seats it was defending on the night, leaving them with 158 seats.

In the 2013 elections in Anglesey, the party won 12 seats, up from the 6 it won in 2008 (although there were significant boundary changes and a reduction in the total number of seats from 40 to 30).

The 2017 figures are based on changes from the 2012 and 2013 elections. (Hence the slight discrepancy in the percentage increase.)

European Free Alliance

Plaid retains strong links with the Scottish National Party (SNP), with both parties' MPs co-operating closely with one another. They work as a single parliamentary group within Westminster, and were involved in joint campaigning, under the banner of a "Celtic alliance", during the 2001 and 2010 general elections. Both Plaid and the SNP, along with Mebyon Kernow of Cornwall, are members of the European Free Alliance (EFA), a European political party for regionalist, autonomist and pro-independence political parties across Europe. The EFA co-operates with the larger European Green Party to form The Greens–European Free Alliance (Greens/EFA) political group in the European Parliament, although the UK is no longer a member of the European Union.

Sections

Plaid Cymru has several official sections and affiliated groups, with the aim of representing all parts of wider society. The official sections of Plaid are as follows:

Plaid Anabledd - Section for the Disabled & Neurodivergent members of the party.

Plaid BME - Section for the BME members of the party.

Councillors' Association - Section for both elected councillors' and encouraging members to stand as a councillor for Plaid Cymru.

Plaid Ifanc - Section for youth and student members of the party.

Merched Plaid - Section for women members of the party.

Plaid Pride - Section for LGBTQIA+, and ally members of the party.

Undeb - Plaid Cymru's network of trade union activists.