Politics · By Amaya Kavya · 2026-07-14 · 12 MIN

Five Prime Ministers Since Brexit: How Britain Lost Its Stability

For most of its modern history Britain changed prime ministers about once a decade and prided itself on dull, steady government. Since the Brexit vote in 2016 it has churned through five leaders, crashed its own bond market, and thrown out the party that had governed for fourteen years. This is how a country famous for stability lost it, and whether it has got it back.

In October 2022 a tabloid newspaper, the Daily Star, set up a webcam pointing at a cheap iceberg lettuce in a blonde wig, next to a framed photo of the prime minister, Liz Truss. The joke, borrowed from a line in The Economist, was simple: would the lettuce outlast her time in office. It did. Truss resigned after forty-nine days, the shortest premiership in the history of the country, and the paper ran the headline "Lettuce wins". A vegetable had become the most reliable measure of British government.

That is a comic image, but it points at something serious. For most of its modern history Britain was known for boring, steady government. It changed prime ministers roughly once a decade. Margaret Thatcher lasted eleven years, Tony Blair ten. The system was designed to hand one party a solid majority and let it govern. Then something broke. Since the Brexit vote in 2016 the country has run through five prime ministers, Theresa May, Boris Johnson, Truss, Rishi Sunak and Keir Starmer. It suspended its own Parliament unlawfully, nearly blew up its pension funds, and in 2024 threw out the party that had governed for fourteen years. This is how a country that sold itself on stability lost it.

It did not start as chaos

Go back to where the run of trouble begins and it looks calm. In 2010 David Cameron became prime minister, first in a coalition and then, from 2015, with a majority of his own. He was a modern, moderate Conservative who wanted to detoxify his party's image. His government's defining choice at home was austerity, a long programme of spending cuts brought in after the 2008 financial crash to shrink the deficit. Schools, councils, police and welfare were squeezed year after year. Living standards, which normally rise, more or less stopped rising. Hold that thought, because it matters later.

Cameron's defining choice abroad was the one that undid him. His party had been quietly at war with itself over Europe for thirty years, ever since Thatcher's fall. On his right, the UK Independence Party, led by Nigel Farage, was pulling Conservative voters away by promising to leave the EU altogether. To settle the argument and protect his flank, Cameron promised that if he won in 2015 he would hold a referendum on membership and let the public decide. He won. He was sure the country would vote to stay. He called the vote to end a fight inside his own party. Instead he lost control of everything.

The vote that split the country in two

On 23 June 2016, Britain voted by 52 percent to 48 to leave the European Union. It was close, and it cut across the usual lines. Older voters, smaller towns and the old industrial areas mostly voted Leave. Cities, the young and Scotland mostly voted Remain. The morning after, Cameron stood outside Downing Street and resigned.

The result did two lasting things. It handed his successors a task that was almost impossible to do cleanly, because "leave" meant a dozen different things to the people who had voted for it, from a light trade change to a total break, and no version could satisfy them all. And it split the country into two camps, Leave and Remain, that cut straight through both main parties. For years afterwards that split, not the old argument between left and right, was the thing that decided everything. A prime minister no longer had to hold a party together. They had to hold together two tribes who did not agree on the single biggest question in politics.

The impossible job

Theresa May inherited that job in the summer of 2016. She was cautious and dutiful, and she almost immediately made her position harder. In 2017 she called an early election expecting to crush a weak Labour opposition and win a big majority to push her Brexit deal through. She lost her majority instead, and had to govern with the support of a small Northern Irish party, the DUP. From then on she did not have the numbers.

What followed was two years of deadlock that made the country look ungovernable. May negotiated a withdrawal deal with the EU and brought it back to Parliament. In January 2019 the House of Commons rejected it by 230 votes, the heaviest defeat of a British government since 1918. A hundred and eighteen of her own MPs voted against her. She brought it back twice more and lost twice more. She could neither pass her deal nor leave without one nor call the whole thing off. In the summer of 2019, worn down, she resigned.

Winning big, then falling apart

Boris Johnson took over in July 2019 promising to break the logjam and "get Brexit done". He governed by force. When Parliament kept blocking him, he suspended it for five weeks, a move the Supreme Court then ruled unlawful by eleven votes to nil, saying he had stopped Parliament doing its job without good reason. He purged rebels from his own party. And in December 2019 the gamble paid off spectacularly. He won a majority of eighty seats, the biggest Conservative win since Thatcher, by taking traditionally Labour seats across the north and midlands that wanted Brexit settled. On 31 January 2020 Britain formally left the EU.

For a moment it looked like stability had returned. It had not. The pandemic hit within weeks. And then Johnson's own conduct brought him down. It emerged that Downing Street had held parties during the lockdowns when the rest of the country was banned from seeing dying relatives. Johnson was fined by the police, the first sitting prime minister ever found to have broken the law in office. The scandals piled up, and in July 2022, after he was caught having promoted a colleague accused of sexual misconduct, his government simply walked out. Sixty-two ministers and officials resigned in under two days. He quit with the line "them's the breaks".

Forty-nine days

The Conservative Party then did something that reveals a lot about how Britain now changes leaders. Because the party was in power, the next prime minister was chosen not by the public but by the roughly 170,000 people who were paid-up Conservative members, a group far smaller and more hardline than the country. They picked Liz Truss, who had promised deep tax cuts and a jolt of growth.

Days into the job she buried the Queen, who died on 8 September 2022. Then, on 23 September, her chancellor announced £45 billion of tax cuts with no plan to pay for them and no independent forecast to check the sums. The markets did not wait for an election to pass judgement. The pound fell to its lowest level against the dollar in history. Government borrowing costs shot up so fast that pension funds, which had quietly built up risky bets on stable bond prices, faced collapse within days. The Bank of England had to step in with an emergency rescue to stop a chain reaction. It was a British government crashing its own economy in a week, with a policy, not a war or a foreign shock. Truss sacked her chancellor, then resigned. Forty-nine days. The lettuce won.

Third prime minister in a year

Rishi Sunak took over in October 2022, the third prime minister that year and the fifth since 2016. He was steadier, a former banker who calmed the markets, but he inherited a party that had been in power for twelve years, exhausted, divided, and blamed for a cost of living crisis, crumbling public services and the Truss disaster. On the right, Farage was back with a new party, Reform UK, pulling votes away exactly as UKIP had a decade earlier.

In July 2024 the reckoning came. Labour, led by Keir Starmer, won a landslide, 411 seats and a majority of 172, and fourteen years of Conservative government ended. The Conservatives were reduced to 121 seats, their worst result since the party took its modern form in the nineteenth century. But look closer and even that landslide was strange. Labour won it on just under 34 percent of the vote, the lowest share any winning party has ever governed on. It was less that Britain had fallen in love with Labour and more that the right had split and the Conservative vote had collapsed and scattered. A huge majority was built on shallow ground.

Why it kept happening

Pull the threads together and the instability is not really about any one leader being weak. It comes from a few deeper things happening at once.

The first is the Brexit fracture. The referendum did not just decide a policy. It cut a new line through British politics that neither party sat comfortably on, and it set a task that could not be finished in a way that pleased the people who demanded it. Delivering it consumed May and defined Johnson, and the promises made to win it, of easy wealth and full control, raised hopes that the reality was never going to meet. When politics runs on promises that cannot be kept, trust drains away, and voters start throwing out whoever is in front of them.

The second is the way Britain removes its leaders. A prime minister is not elected directly. They lead the largest party, and that party can remove them between elections, with no public vote at all. Three of the five, May, Johnson and Truss, were pushed out by their own side rather than by the electorate. It makes leaders disposable and encourages MPs to treat a bad month as a reason to change the person at the top, again and again.

The third is the economy underneath it all. Since the 2008 crash, wages and living standards in Britain have barely grown, one of the longest stretches of stagnation in modern memory. Austerity thinned out the public services people rely on. Then came the pandemic, then a spike in energy prices, then the cost of living crisis. When people feel poorer year after year, they punish whoever holds office. That anger does not attach to one party. It hits each government in turn, which is exactly what a decade of one-term-feeling prime ministers looks like.

Has it ended?

The easy story is that the 2024 landslide drew a line under the chaos and returned Britain to normal, dull, majority government. It might. A large majority does give Starmer the numbers that May and Johnson and Sunak lacked at various points, and that alone buys stability.

But the ground has not healed. A government elected by a third of voters, over a public that is tired and distrustful, with a resurgent hard-right party snapping at both main parties and living standards still under strain, is not the settled Britain of the Blair or Thatcher years. The forces that broke the last decade, a fractured electorate, stagnant incomes, and parties that turn on their own leaders the moment the polls dip, are all still there. The lettuce has been thrown away. Whether the thing it was mocking has gone with it is a different question, and the honest answer is that nobody in Westminster yet knows.

Sources

Delvewire