Brexit Hangover: How Populism Continues to Shape Britain’s Politics and Foreign Policy
Nearly a decade after the Brexit referendum, the populist forces that fueled Britain’s departure from the European Union (EU) continue to shape both domestic politics and foreign policy, particularly through anti-immigration rhetoric. Populist narratives centered on anti-elitism, nationalism, and immigration have become deeply embedded across both mainstream and fringe parties, influencing the United Kingdom’s (UK) domestic political climate and creating potential spillovers into international decision-making.
Populism frames society as a struggle between the “common people” and a corrupt or out-of-touch “elite,” with leaders claiming to represent the “will of the people” against established institutions and norms. In recent years, the most successful populist movements have emerged on the right and far-right. Figures like Donald Trump in the United States, Marine Le Pen in France, and Nigel Farage in the United Kingdom have paired populist rhetoric with anti-immigrant sentiment, nationalism, and at times, authoritarian tendencies.
Populist headwinds prevailed in the UK’s 2016 EU exit referendum. By a narrow four-point margin, British voters opted to leave the EU. The referendum was characterized by a rising force of populism that stemmed from a widespread inclination to constrict immigration and reassert national sovereignty over international institutions. The referendum, held on June 23, 2016, initiated the process of Brexit, culminating in the UK’s formal withdrawal on December 31, 2020.
The Great Recession played a pivotal role in shaping this populist backlash. The crisis made it straightforward for many to identify the “elite” as responsible for the financial turmoil that disproportionately harmed the working class. The quarterly unemployment rate reached 8.4 percent in 2011, its highest rate since 1995. This economic discontent coincided with rising immigration levels, leading to a false correlation between immigration and economic decline. While Britain’s economy was largely absorbing immigrants effectively, perceptions proved more powerful than data.
Dani Rodrik, a professor of International Political Economy at Harvard’s Kennedy School of Government, added another perspective, stating, “The perceived threat of mass inflows of migrants and refugees from poor countries with very different cultural traditions aggravates identity cleavages that far-right politicians are exceptionally well placed to exploit.” Whether it was residual frustration with economic conditions or fears of cultural change, British voters were primed to direct their blame towards minorities, immigrants, and the establishment and institutions.
The victory for the Leave campaign accompanied prevalent anxiety about terrorism and Islamic extremism, exacerbated by the November 2015 Paris attacks and the March 2016 Brussels bombings. In 2018, Leave.EU, a major group broadly credited for the 2016 referendum victory of the campaign to leave the EU, drew condemnation for a tweet in which they claimed the Labour Party to be “reliant on the votes of Britain’s exploding Muslim population.” Critics slammed the tweet for populist messaging that had crossed into “anti-Muslim bigotry.” Discussing the catalysts for Brexit, Bart Bonikowski, a professor of sociology at Harvard University at the time, pointed to the “growing ability of political elites to channel public grievances into ethnoracial resentment and political distrust.”
Nearly a decade after the Brexit referendum, the populist narratives that fueled the Leave campaign remain deeply embedded in British politics. According to polling by YouGov, the right-wing populist Reform UK party would be Britain’s largest political party if a general election were held today, reflecting the persistence of Brexit-era populism. This would put the party’s founder, Nigel Farage, on a potential course to become the country’s next prime minister.
Originally founded in 2018 as the Brexit Party, the party’s initial goal was to advocate for a no-deal Brexit, a complete withdrawal of the UK from the EU without a formal agreement. Rebranded as Reform UK, the party has since evolved from a fringe movement into an increasingly formidable presence within Britain’s fragmented right. In the 2024 parliamentary elections, Farage finally secured a seat in parliament on his eighth attempt, symbolizing the party’s entry into mainstream politics.
Reform’s populist appeal draws strength from the perception that Britain’s two dominant parties of the past century, Labour and the Conservatives, are part of an elitist class that fail to deliver their political promises. YouGov polling in September 2025 found that 66 percent of Britons viewed Labour as disconnected from the average citizen. Just 11 percent viewed the Conservatives as ready to govern. Populist messaging continues to resonate with disillusioned voters. In October of 2025, 20 Tory councillors defected from their party to Reform. In addition, according to research by Reuters, Reform has “successfully poached at least 80 former candidates, donors and staff members” from the traditional right.
At the core of Reform’s platform lies a hard-line stance on immigration, the same issue that animated much of the Brexit campaign. The party pledges to freeze all “non-essential” immigration and to block small boats carrying undocumented migrants and refugees from crossing the English Channel. In doing so, Reform UK has effectively re-weaponized the populist themes of sovereignty, border control, and cultural preservation that defined 2016, ensuring that the Brexit mindset continues to dominate the British political imagination.
Immigration remains a pervasive and effective motivator in British politics. It has consistently polled among the public’s top concerns, with figures showing asylum claims at record highs in 2025. This surge reignited tensions mirroring the pre-Brexit years, triggering widespread anti-migrant protests in August 2025 outside hotels housing asylum seekers. In September 2025, between 110,000 and 150,000 people protested against immigration and joined the right-wing “Unite the Kingdom” demonstration in London, which resulted in some violent clashes with law enforcement. These outbursts reveal how the political and cultural fault lines of Brexit, particularly around national identity and immigration, continue to dominate Britain’s domestic climate.
Mainstream parties have struggled to respond effectively to this enduring populist pressure. When Prime Minister Keir Starmer assumed the premiership in July 2024, ending 14 years of Conservative rule, he faced the daunting task of proving that his center-left Labour government could reverse Britain’s populist drift. Attempting to placate the populist desires of the electorate, Starmer in May announced an effort to restrict immigration, stating in a policy paper that, “The damage [immigration] has done to our country is incalculable.” However, slow economic growth, persistent inflation, and the escalating immigration crisis have quickly eroded his political standing. A recent Ipsos opinion poll found that only 13 percent are satisfied with his performance.
Although the next general election is not required until 2029, Starmer’s political vulnerability has created questions about Britain’s future direction. A Reform UK-led government would mark a fundamental rupture from the international outlook of its predecessors. The party’s Eurosceptic base and nationalist rhetoric suggest a retreat from traditional alliances. In early 2025, a third of the party’s base expressed a desire to cut aid for Ukraine if the United States did so. Farage himself drew criticism in June 2024 from both Conservative then-Prime Minister Rishi Sunak and Labour Leader Keir Starmer for comments he made claiming the EU and the North Atlantic Treaty Organization (NATO) had “provoked” Russia’s invasion of Ukraine.
While Reform’s laser focus on immigration has delivered short-term political traction, it risks building Britain’s foreign policy around resentment not vision. This approach shies away from confronting the broader challenges the UK faces, including economic pessimism driven by a cost-of-living crisis and an unclear future relationship with Europe. The result is a country still trapped in the logic of Brexit, where external engagement serves domestic identity battles more than coherent global aims.
The populist momentum that carried Brexit to victory continues to reverberate through British politics. The rise of Reform UK, accompanied by persistent public anxieties over immigration and the ongoing challenges faced by mainstream parties, demonstrates that domestic populism is increasingly shaping Britain’s foreign policy, often at the expense of a coherent long-term strategy. The question now is whether Britain can move beyond the populist impulses of the Brexit era before they come to define its political and global identity.