Populist, authoritarian and extremist parties secured more than half the vote in the latest parliamentary elections in Bulgaria, Czechia, Romania and Slovakia, while their combined support across Europe reached a record 32.6%, according to a report by Swedish think tank Timbro and the EPICENTER network published this week.

Italy is the only other country among the 31 European democracies covered where so-called challenger parties command a majority, and seven of the 10 countries where they are strongest are post-communist, the fifth edition of the Authoritarian Populism Index found. Challengers won more than 20% of the vote in 26 countries, with almost one in three European voters backing parties classified as populist, authoritarian or extremist — roughly three times the level seen for most of the post-war era.

The report, authored by Andreas Johansson Heinö, examines more than 260 parties using electoral data dating back to 1945 and includes a detailed analysis of 76 parties. It finds that the radical right is driving most of the increase, retaining support rather than fading after protest surges, while the radical left has edged up recently but remains well below its post-war strength. Social democrats have lost more than four in 10 voters since 2000, while Christian democrats have declined steadily since the 1970s. Liberal parties, by contrast, remain close to their record levels of support.

Challenger parties are also increasingly part of the political establishment. By summer 2026 they were represented in 11 of the 31 governments covered, although participation in power has produced different outcomes, moderating some parties, emboldening others and contributing to the collapse of coalitions elsewhere.

Central and Southeast Europe has supplied some of the clearest examples of the risks to liberal democracy. Of the 76 parties examined in depth, 18 are classified as highly authoritarian, including Hungary's Fidesz, Poland's Law and Justice (PiS) and Slovakia's Smer. These parties have "already demonstrated in government how far they are prepared to go in weakening judicial independence, constraining media pluralism, politicising state institutions or otherwise eroding liberal-democratic checks and balances", Johansson Heinö wrote.

Hungary also illustrates the limits of the model. Peter Magyar's newly founded centre-right Tisza won 53.2% of the party-list vote in the April election against 38.6% for Fidesz, securing 141 of 199 seats and ending Viktor Orban's 16 years in power. The report describes Fidesz as one of Europe's clearest examples of authoritarian populism developing within an electoral democracy, but notes that voters were able to remove it despite highly unequal conditions of competition. The radical-right Our Homeland Movement survived the realignment, winning 5.6% of the list vote.

In Czechia, Andrej Babis' ANO returned to power with 34.5% of the vote in 2025 and governs alongside the radical-right Freedom and Direct Democracy (SPD) and the Motorists for Themselves. The coalition marks the first time the modern Czech radical right has entered national government.

The government has shifted policy towards a more sovereignty-oriented line, cutting defence spending and scaling back support for Ukraine. Its plan to replace the licence fee for public broadcasters with direct state funding has also drawn mass protests. However, the index rates ANO as less authoritarian than Fidesz or Smer.

Slovakia's government under Robert Fico has moved further towards an illiberal national-conservative position. Smer has evolved from a pragmatic left-populist party into one with "a conception of sovereignty resembling that promoted by Viktor Orban in Hungary", the report says. It points to Fico's decision to end official military aid to Ukraine and his repeated meetings with Russian President Vladimir Putin, most recently in Moscow in May.

Coalition partner Hlas has been pulled towards Smer, while the hard-right, pro-Russian Republika won 12.5% in the 2024 European Parliament election.

In Romania, George Simion's Alliance for the Union of Romanians (AUR) has led the polls for much of the past two years. It is classified as highly authoritarian, as are the smaller S.O.S. Romania and the Party of Young People.

The index also counts the Social Democratic Party (PSD), which joined AUR in the no-confidence vote that brought down Ilie Bolojan's government in May, because of its populist and authoritarian traits. Simion has since threatened to move against President Nicusor Dan unless he calls a snap election.

Bulgaria presents a different type of challenger. Former president, now prime minister, Rumen Radev's Progressive Bulgaria, founded in March, won an outright majority in the 2026 parliamentary election after eight elections in four years. The report considers the party broadly mainstream on policy but populist in style, with a focus on corruption and oligarchic interests. Many observers compare Radev with Orban and Fico because of his calls for a more pragmatic relationship with Russia, a comparison he rejects. Radev's ally Iliana Yotova leads the race for the presidential election on October 25.

Poland's right has fragmented. Konfederacja has established itself as a substantial independent force, while Grzegorz Braun's Confederation of the Polish Crown now advocates leaving the EU. PiS suffered its biggest split in more than 20 years in July, when former prime minister Mateusz Morawiecki and dozens of supporters left to form the Rozwoj Plus group, which has around 40 MPs.

The report argues that Russia has become a new dividing line on the European right. Orban obstructed or delayed EU measures against Moscow while in office, while disagreements over Ukraine helped split Estonia's radical-right EKRE in 2024. Ties to US President Donald Trump's Make America Great Again (MAGA) movement have not delivered the electoral boost many expected, and Orban's defeat came despite almost unanimous backing from Europe's radical right.

The divide reflects a broader shift in the movement's priorities. Of the 76 parties examined in detail, 20 are classified as hard eurosceptic, making outright EU exit a minority position. Many now seek to reshape the bloc from within, redirecting cooperation towards migration control, border protection and national sovereignty.

The report's central concern remains the effect of these parties on democracy when they enter government, rather than their electoral success alone. Their records show that holding office can moderate some challengers but can also give others greater scope to weaken institutional checks and balances.