Welsh independence (Welsh: Annibyniaeth i Gymru) is a political ideal advocated by some political parties, advocacy groups, and people in Wales that would see Wales secede from the United Kingdom and become an independent sovereign state. This ideology is promoted mainly by the Welsh nationalist party, Plaid Cymru, and the non-party YesCymru campaign.
Wales became distinct culturally and politically from other Brythonic groups during the Early Middle Ages. Following the Norman conquest of England in 1066, the Normans penetrated into Wales and gradually established control over parts of the country. The death of Llywelyn ap Gruffudd in 1282 led to the conquest of the last independent Welsh kingdom by Edward I of England. The Welsh revolted against English rule several times over the next years, with the last significant attempt being the Glyndŵr Rising of 1400–1415, which briefly restored independence. In the 16th century Henry VIII, himself of Welsh extraction, passed the Laws in Wales Acts aiming to incorporate Wales fully into the Kingdom of England. For centuries, the union was considered to be an advantage to Wales, and it offered new opportunities to the Welsh gentry who could now become justices of the peace and members of Parliament at Westminster.
According to the Encyclopaedia of Wales, the belief that Wales should form an independent nation state originated in the mid 19th century (the first recorded use of the Welsh word for nationalism, cenedlaetholdeb, is from 1858). The Sunday Closing (Wales) Act 1881 was the first legislation to acknowledge that Wales had a separate politico-legal character from the rest of the English state. In 1886 Joseph Chamberlain proposed "Home Rule All Round" the United Kingdom, and in the same year the Cymru Fydd (Young Wales) movement was founded to further the cause. However, the goal they envisaged was a devolved assembly rather than a fully independent state, and the movement collapsed in 1896 amid personal rivalries and rifts between representatives from the North and South, East and West Wales.
There was little mainstream political interest in Home Rule following the First World War. The focus of Welsh nationalist politics moved to the newly founded Plaid Cymru from 1925, although it took until the late 1960s for Plaid to make its first electoral breakthroughs. In 1956 a 250,000-name petition calling for a parliament for Wales produced few results, but the declaration of Cardiff as the capital of Wales in 1955, Labour's 1959 commitment to appoint a Secretary of State for Wales, the creation of the Welsh Office in 1965, and the repeal of the Wales and Berwick Act 1746 two years later seemed to demonstrate a growing nationalist impetus. However, the heavy defeat for a proposed Welsh Assembly offered by Labour in the 1979 devolution referendum "suggested that the vast majority of the inhabitants of Wales had no desire to see their country having a national future".
In the 1980s, economic restructuring and Thatcherite market reforms brought social dislocation to parts of Wales, which had formerly been described as having "the largest public sector west of the Iron Curtain". A succession of non-Welsh Conservative Secretaries of State after 1987 was portrayed by opponents as 'colonial' and indicative of a 'democratic deficit'. In the early 1990s the Labour Party became committed to devolution to both Scotland and Wales, and in 1997 it was elected with a manifesto commitment to hold referendums on a Scottish Parliament and a Welsh Assembly.
The proposed assembly won a narrow majority in the 1997 referendum. The political climate was very different from that of 1979, with a new generation of Welsh MPs in Westminster and a broad consensus on the previously divisive issue of the Welsh language. However, political commentator Denis Balsom notes public sentiment that devolution may have been "unnecessary" following the election of a 'progressive' Labour Government. These conflicting sentiments were reflected in the relatively low turnout at the referendum and the narrowness of the victory for devolution campaigners. Since 1997, there is evidence of increased support for, and trust in, the Assembly and greater support for it to receive enhanced powers, as evidenced by the 63.49% "Yes" vote in the 2011 referendum.
Following the announcement in 2017 of plans to hold a second referendum on Scottish independence, Plaid Cymru leader Leanne Wood said there needed to be a national debate on Welsh independence.
Surveys regarding support for independence have yielded different results, though they often find that between 10 and 25% of Welsh people desire independence from the United Kingdom. A 2001 survey for the Institute of Welsh Affairs found that 11% of people polled favoured independence. A 2007 survey by the Institute of Welsh Politics at the University of Wales found that 12% of those questioned supported independence, down slightly from 14% in 1997. A poll taken by BBC Wales Newsnight in 2007 found that 20% of Welsh questioned favoured independence. A 2006 poll taken by Wales on Sunday found the number to be as high as 52%, although the poll mostly interviewed people in North Wales and West Wales where support for independence is strongest.
A Yougov/ITV Wales Poll in February 2012, showed that only 10% of Welsh voters would support independence even if Scotland became independent of the British state, with three constituent countries, the same level of support as polls have shown with the British state composing four constituent countries. However, a Yougov/ITV Wales Poll in September 2014, showed a marked increase in support for Welsh independence having risen to 17%.
In February 2014, an ICM poll for BBC Wales found that 5% of people wanted to see an independent Wales. Following the referendum on Scottish independence, a September 2014 poll conducted by the same company found that support for Welsh independence had remained relatively unchanged from the previous poll in February, recorded as being at 3%. The same poll found that there had been a significant increase in support for more powers for the Welsh Government.
In March 2016, the political party Cymru Sovereign was established. The party seeks Welsh independence from the United Kingdom, as well as Welsh independence from the European Union (EU). The party also seeks the creation of a publicly owned Central Bank of Wales and the creation of a Welsh pound currency. The leader of the party secured 38 votes (last place, 0.1%) out of the 27,751 cast in the 2016 Welsh Assembly constituency election for Newport West 
It had been suggested before the UK's referendum on European Union membership that Wales might vote by a majority for Remain while the UK as a whole voted for Leave, which would increase support for independence. However, while Scotland and Northern Ireland voted for Remain, Wales as a whole voted by a majority for Leave, with majorities for Leave in all but five of its council areas, the Remain majorities being in Cardiff, Monmouthshire, Vale of Glamorgan and the Welsh-speaking heartlands, Gwynedd and Ceredigion. Subsequent studies have suggested, however, that the voted was tilted in favour of Brexit by English retirees moving to Wales, without which Wales would have voted to Remain 
A poll commissioned by YesCymru in May 2017 found of the major political parties in Wales that Labour voters and Plaid Cymru voters, as well as those aged 18–49, were most likely to vote for independence, while UKIP and Conservative voters were least likely. It also found that 5⁄6 of Plaid Cymru voters favoured independence, and that Welsh speakers were three times more likely to favour independence.
On 11 May 2019, a march for Welsh independence was organised by AUOB Cymru in Cardiff, with an estimated 3,000 in attendance. On 27 July 2019, AUOB organised an independence march in Caernarfon. Estimates put the attendance at about 8,000. On 7 September 2019, a third AUOB Cymru was held in Merthyr Tydfil and attracted a crowd of 5,200.
|Date||Support independence (%)||Support more powers for the National Assembly (%)||Support status quo (%)||Support fewer powers for the National Assembly (%)||Support abolition of the National Assembly (%)||Indifferent/Did not reply/Other (%)|
|December 2018 ||8||40||23||4||18||7|
|7–23 February 2019 ||7||46||27||3||13||4|
|Date(s) conducted||In Favour of Independence||Opposed to Independence||Indifferent/No Reply||Sample||Held by||Notes|
|March 2013||10%||62%||28%||Unknown||ITV Wales/ YouGov||Even if Scotland left.|
|April 2014||16%||62%||22%||1,000||You Gov|
|8–11 September 2014||17%||70%||13%||>1,000||ITV Wales/Cardiff University|
|July 2016||15%||65%||20%||1,010||ITV Wales/ YouGov|
|July 2016||19%||61%||21%||1,010||ITV Wales/ YouGov||Even if Scotland left.|
|July 2016||28%||53%||20%||1,010||ITV Wales/ YouGov||Independent Wales within the European Union.|
|30 May – 6 June 2018||19%||65%||16%||2,016||YouGov||Respondents asked "Do you agree that Wales should become an independent country?"|
|7–14 December 2018||17%||67%||16%||1,014||Sky News Data- Wales ||Respondents asked "If there were a referendum tomorrow on the issue of Wales becoming an independent country, how would you vote?"|
|6–10 September 2019||24%||52%||23%||1,039||Plaid Cymru/YouGov ||Respondents asked "If there was a referendum held tomorrow on Wales becoming an independent country and this was the question, how would you vote? Should Wales be an independent country?"|
|6–10 September 2019||33%||48%||20%||1,039||Plaid Cymru/YouGov ||Respondents asked "Imagine a scenario where the rest of the UK left the European Union but Wales could remain a member of the European Union if it became an independent country. If a referendum was then held in Wales about becoming an independent country and this was the question, how would you vote? Should Wales be an independent country?"|
|10%||2%||6%||6%||5%||18%||4%||6%||7%||5%||31%||1,000||Yes Cymru/ YouGov||Respondents asked to rate 0–10.|
0–4 Against, 5 indifferent, 6–10 in favour. Don't know removed.
|14%||4%||5%||6%||7%||17%||5%||6%||6%||2%||28%||1,133||YesCymru/ YouGov||Respondents asked to rate 0–10.|
0–4 Against, 5 indifferent, 6–10 in favour. Don't know removed.
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