The United Kingdom held a bumper set of local and national elections last week, on what British media dubbed “Super Thursday,” including a set of elections delayed by a year because of the first COVID lockdown. This midterm vote gave the British people a chance to have their say on the records of Prime Minister Boris Johnson and the new Labour leader Sir Keir Starmer for the first time since the pandemic began. One of the most significant results of the night came from the post-industrial town of Hartlepool in the North East of England.

A few months ago, the Labour member of parliament (MP) for Hartlepool resigned after allegations of sexual harassment became public, triggering a by-election to take place alongside the other elections on May 6. In the biggest by-election win for a governing party in history, the Conservatives gained the seat with double the Labour vote, scoring over 50 percent of the total. Hartlepool has almost always been represented by Labour MPs since 1945, except for 1959 when a Conservative was elected for a single term with a wafer-thin majority.

In the middle of a global pandemic, it is surprising for a governing party to do so well, especially in the heartlands of the main opposition party. It is another sign of how British politics has changed since the vote to leave the European Union. Almost 70 percent of Hartlepool voted for Brexit in 2016, but the Conservatives struggled to win the seat in the 2017 and 2019 general elections. The presence of populist parties, first the U.K. Independence Party and then the Brexit Party, split the Brexit vote in the seat. But now that Boris Johnson has fulfilled his promise to “get Brexit done,” the Conservatives have taken the seat at last.

North East England is becoming a Conservative stronghold after a century of Labour dominance. Northumberland’s local council is under Conservative control for the first time since 1970 and Labour lost control of Durham County Council for the first time since 1925 after the Conservatives gained 14 seats. The Conservative Mayor of Tees Valley was re-elected with almost 73 percent of the vote. Across the rest of provincial England, the Conservatives also gained new council seats. There were even swings towards the Conservatives in London where Labour was expecting an easy victory.

A bounce in popularity from the successful vaccine rollout has certainly played a role in the Conservatives’ success but it does not explain the long-term trends represented by these results. Brexit created a unique opening for the Conservatives, traditionally the party of the South of England, to make major inroads in Labour’s northern heartlands. In the years following the Brexit vote, most of the Labour party, including its present leader, tried to stall or reverse the referendum result against the wishes of their working-class voters. Labour paid a heavy price for this in 2019 when Boris Johnson won an 80-seat majority, demolishing much of Labour’s “Red Wall” in the North of England. But with Brexit done, the Conservatives are now trying to secure sustained success with working-class voters.

Boris Johnson won the E.U. referendum and the 2019 general election by speaking to working-class voters’ sense of being neglected and taken for granted by Westminster, including the Labour Party. He promised to deliver change for the North and “level up” the country with new investment for public services and infrastructure ahead of cutting taxes and red tape. Addressing the inequalities created by globalization and the financial crisis has been given new urgency by the pandemic. Re-election in 2024 will depend on the Conservatives’ ability to secure a strong economic recovery that benefits working-class communities.

This challenge to narrow the inequalities between North and South is bigger than Boris Johnson, Brexit and the pandemic. It is a structural divide that has endured throughout English history since Roman times. The affluent, well-educated, and resource-rich South has been the home of England’s elites and powerbrokers for centuries. It was the North that repeatedly put up the most resistance to elites based in the South, whether it be Roman invasion, Norman occupation, or the Protestant reformation.

After Catholic nobles rebelled against the Protestant Elizabeth I in 1569, the power of the Crown was fully asserted in the North, destroying the power of the northern aristocracy. The impact of this defeat would persevere into the next century when the North rallied to the Royalist cause in the fight against the Parliamentarians during the English Civil War. It was not until the birth of the Industrial Revolution in the North that the region was able to fully acquire economic prestige and political influence that could rival the South.

As Catholicism went into retreat, the North also found a new and distinct identity in nonconformist religion and radical politics. Reformers sprung up to advance causes such as parliamentary reform, religious toleration, and workers’ rights. The 1819 “Battle of Peterloo” in the northern city of Manchester, where pro-reform protesters were fired upon by government soldiers, became a symbol of oppression by southern elites. It is this deep history of rebellion, protest, and reform that ultimately created the Labour Party in 1900 to represent the interests of the English working class.

Although the Conservatives have made occasional breakthroughs in the North, Prime Minister Margaret Thatcher’s program of free-market reform and success in defeating the 1984 Miners’ Strike made the Conservative brand toxic across the region’s deindustrialized communities. It is these same communities that are now abandoning Labour and helping the Conservatives to expand their pro-Brexit coalition. Around 39 Labour seats that Boris Johnson could not win in 2019 because of the Brexit Party, which has since collapsed in support, could turn Conservative in the next general election.

A chink in the Conservatives’ armor, however, has been exposed by “Super Thursday.” Many affluent southern seats that have gone to the Conservatives since 2010 and voted to remain in the E.U. are now trending leftwards. The threat of former Labour leader Jeremy Corbyn entering Downing Street and enacting a radical far-left agenda was enough to keep these seats in Conservative hands in 2019. Last week, Labour gained mayoralties and council seats in these places. But by becoming the party of metropolitan and suburban England, Labour is losing its working-class roots and struggling with an existential crisis.

“Super Thursday” has also set up the Conservatives for another historic constitutional problem. Despite the Scottish National Party’s failure to win an outright majority in the Scottish Parliament, First Minister Nicola Sturgeon will still press ahead with her demands for a second independence referendum. Boris Johnson will have to fight to save the Union between Scotland and England as well as healing the North-South divide. This is a flashpoint in history that will determine exactly what kind of nation England will become.

David A. Cowan is a writer based in London, and is a graduate of the University of Cambridge.