On May 7, voters across the United Kingdom will elect new local councils, municipal authorities, and devolved national governments. These elections—don’t call them the British midterms—could be seismic.

It is starting to look as if the two-party Westminster system, the Labour Party and Conservative Party duopoly that has dominated U.K. politics for more than a century, is coming apart. Anti-establishment sentiment takes on a slightly different form in each constituent part of the U.K.; collectively, these trends could weaken British political unity.

In England, Labour and the Tories are losing support on the right to Nigel Farage’s Reform UK and on the left to Zack Polanski’s ecosocialist Green Party. The separatist Scottish National Party (SNP) is on course for a fifth consecutive victory at Holyrood, Scotland’s semi-autonomous parliament, while Reform could push Labour, once the dominant party, into third place. Finally, in Wales, the center-left nationalist Plaid Cymru is surging alongside Reform.

It’s worth putting all of this in perspective. In the 1997 general election, the Labour Party and the Conservatives secured more than 23 million votes between them, or 74 percent of all votes across the U.K.—leaving smaller parties, including the SNP and Plaid, with barely more than one-quarter of the vote. (At the time, the far-right Reform didn’t exist, and the Greens were marginal.) Today, Labour and the Tories are polling at just 15 and 16 percent, respectively. Meanwhile, Reform clocks in at 25 percent and the Greens at 21 percent.

In other words, nearly three decades after Tony Blair’s era-defining Labour victory in the late 1990s, British voting patterns have altered beyond recognition. The principal political casualty of this shift will be incumbent Labour Prime Minister Keir Starmer, whose public standing has collapsed at lightning speed.

Starmer entered Downing Street in July 2024 on a pledge to “renew” the U.K. after 14 years of Conservative misrule. Compared with his exhausted Tory counterparts—who in that time had imposed on the country austerity, Brexit, and Boris Johnson and Liz Truss as prime ministers—the Labour leader looked fresh. A centrist lawyer with establishment credentials and a reputation for institutional competence, Starmer promised to restore stability and to rule in a way that would, in his words, “tread more lightly” on the lives of ordinary citizens. Instead, his administration has blundered from one crisis to the next.

Shortly after Starmer took office, Chancellor of the Exchequer Rachel Reeves announced plans to strip some British pensioners of their state-funded winter fuel allowances, seeking to slash a multibillion-pound budget deficit. Labour lawmakers revolted, and Reeves backed down. But by that point, Reeves was in another fight with her own party, this time over her refusal to scrap the two-child benefit cap, a Tory-era reform that restricted the access of British families with more than two children to supplementary welfare support. Again, Reeves’s party colleagues protested, and she demurred—weakening Starmer, who had authorized these cuts.

Starmer’s prospects deteriorated further at the start of this year, as the full scale of the Peter Mandelson affair unfurled before the public. In December 2024, Starmer appointed Mandelson, a long-term fixer in the Blairite contingent, to the country’s most prestigious diplomatic position: the U.K. ambassador to the United States. Starmer made the decision fully knowing that Mandelson was once friends with convicted sex offender Jeffrey Epstein. Last year, new messages revealed the extent of that friendship, and Mandelson was sacked.

When subsequent reports suggested that Mandelson shared sensitive government information with Epstein, potentially compromising national security, public anger turned on Starmer, who issued a faltering apology in Parliament for the appointment. It came too late: The scandal ripped through Starmer’s government, prompting key figures to resign, including Downing Street Chief of Staff Morgan McSweeney, a Mandelson protege who had orchestrated Starmer’s rise from back-bench Labour parliamentarian in 2015 to leader of the opposition in 2020.

The first controversy, over welfare reform, damaged Starmer’s credibility. The second, over Mandelson, destroyed it. In recent weeks, Labour insiders have begun mapping out Starmer’s exit. In the party, the press, and the public at large, there is a growing expectation that his premiership will soon be over.

Assuming the polls hold—and they have barely changed for weeks—this week’s elections will turn that expectation into reality. The Labour Party looks set to suffer at every level. It is on track for its worst-ever local election performance in England, with some polls suggesting it could shed 74 percent of the roughly 2,500 council seats it is defending. In Scotland, the party is bracing for its weakest result since the creation of the Scottish Parliament in 1999. It will almost certainly lose power in the Welsh Parliament, the Senedd, for the first time in 27 years.

Labour’s defeat will carry constitutional implications for the U.K. as a whole. The SNP is moving into a third decade of political dominance at Holyrood. Under the leadership of John Swinney, the party is preparing the ground for a fresh tilt at independence. Swinney, who served as former Scottish First Minister Nicola Sturgeon’s deputy, wants a second referendum on self-government in 2028. Among Scottish voters, enthusiasm for independence regularly hits more than 50 percent, up from 45 percent in 2014, when Scotland voted against separating from the United Kingdom.

Given the U.K. government’s opposition to another referendum, Swinney’s road to independence is yet unclear. Holyrood needs Westminster’s consent to hold another politically binding vote, and the SNP—keen to secure legitimacy from the European Union—won’t declare independence unilaterally. Still, the simple fact of a staunchly nationalist government in Edinburgh will further destabilize British politics in the coming years.

Add to this growing demands for greater autonomy in Wales, highlighted by Plaid’s polling surge, and even the prospect of a border poll on Irish reunification—the Irish Republican Sinn Fein became the largest party in Northern Ireland’s devolved assembly in 2022—and the unionist foundations of the British state start to look shaky. Notably, both Farage and Polanski are open to Scotland revisiting the question of independence; indeed, Polanski actively encourages it.

It’s possible that Starmer’s position would be more robust were the U.K. not haunted by a sense of social and economic stagnation. Since the 2008 financial crisis, real incomes in Britain have grown slowly, weighed down by “the longest pay squeeze in modern history,” according to the Trades Union Congress. At the same time, living standards have slumped under the weight of high inflation and sticky interest rates; public services, fragmented by decades of privatization, have become increasingly dysfunctional.

The sluggish economy has compounded public pessimism. In 2022, the year in which the U.K had three prime ministers, just 24 percent of Britons said they had confidence in the government. That figure put Britain on par with historically unstable states such as Brazil and Italy in terms of public trust in political institutions. In reality, any prime minister would have struggled in the face of these challenges. But with his litany of scandals, rigid bureaucratic style, and compulsive U-turning, Starmer has turned out to be uniquely ill-suited to manage them.

The Conservative Party is also likely to post heavy losses on May 7. Voters view the Tories, who held power between 2010 and 2024, as complicit in the country’s decline. But it will be the pummeling of Labour that demonstrates the intensity of Britain’s anger.

When Starmer was elected, many liberals initially embraced him as the savior of the British establishment. In the eyes of these enthusiasts, Starmer would restore order following the compound disruptions of the 2014 Scottish independence referendum, Brexit, Corbynism, and the COVID-19 pandemic. He was backed by Blair, the high priest of British centrism, and enjoyed widespread support among British finance luminaries. In a word, Starmer was moderate—to a fault.

Yet here he stands, on the brink after less than two years in office. The truth is that Starmer’s mandate was always fragile. Owing to the vagaries of Britain’s first-past-the-post system, the Labour Party won 63 percent of the seats in the House of Commons with just 34 percent of the vote in the 2024 general election—the smallest-ever vote share for a prime minister taking office. Compared with 2019, turnout sank by nearly 8 percentage points and Labour shed half a million votes. Starmer was an instrument to dislodge the Tories. But he never connected with the electorate; this marriage of convenience has now run its course.

Starmer may leave office immediately, or he may linger on into the summer. Labour doesn’t have an immediate replacement lined up, and the internal succession battle is likely to be intense. Regardless, this week’s elections will signal a new dawn for nationalist and populist parties across the United Kingdom. The great British electoral realignment is about to begin.