Mark Williams, then-Leader of the Welsh Liberal Democrats, was defeated at the 2017 general election in his Ceredigion constituency by Ben Lake of Plaid Cymru, whose majority of 104 made the seat one of the most marginal in the country.

Through politicians such as T. E. ("Tom") Ellis and David Gee and the movement of Cymru Fydd (Wales to be [future]) Welsh nationalism was comparable at times to that occurring in Ireland.

But in Wales the nationalist passion never spilled over into violence, and was also counterbalanced by the strong English Liberal capitalist base present within the party.

When the last of the post-war Welsh Liberal MPs, Roderic Bowen (Cardiganshire), lost his seat in the 1966 general election Hooson, Lord Ogmore, Martin Thomas (Lord Thomas of Gresford), Roger Roberts (Lord Roberts of Llandudno) and Mary Murphy established the Welsh Liberal Party as a separate state party[clarification needed] within the Liberal Party's federal structure.

The arrival of the Social Democratic Party (SDP) in Wales and the formation of the SDP–Liberal Alliance gave the party an electoral boost, increased its representation on councils and helped retake the Montgomeryshire seat in 1983 (Alex Carlile) and win the Brecon and Radnor seat in a famous by-election in 1985 (Richard Livsey).

They were joined in that campaign by other prominent figures in the Welsh party, including Michael German, Jenny Randerson, Peter Black, Roger Williams and Rob Humphreys.

In this Labour-led government Michael German was Deputy First Minister whilst Jenny Randerson also held a ministerial post.

Randerson's post made her the first female Liberal in the party's history to hold ministerial office.

In 2008 German stood down as leader and was replaced by Kirsty Williams (the AM for Brecon and Radnor) in a contest with Jenny Randerson (Cardiff Central).

In September 2012, Baroness Randerson was appointed as the unpaid Parliamentary Under Secretary of State at the Wales Office.

[8] In the autumn of 2017, the leadership election was held, with two candidates, Jane Dodds and Elizabeth Evans, taking part.

In August 2019, Dodds regained House of Commons representation for the Welsh Liberal Democrats, winning the 2019 Brecon and Radnorshire by-election.

[10] However her stay in the House of Commons proved to be a short one, as she lost her seat by 7,131 votes at the December 2019 general election.

[12] In the aftermath of the result, BBC Wales' Political Editor Felicity Evans stated that the Lib Dems would "rue the day they pushed for this election".

In March 2024, the leader of the Welsh Liberal Democrats, Jane Dodds said that the party will not join any coalition after the next UK general election,[15] at that election the party saw its share of the vote increase with David Chadwick winning the newly redrawn seat of Brecon, Radnor and Cwm Tawe.