The crisis of traditional parties in Europe has acquired another example in Sweden. The Social Democratic Party (Socialdemokraterna) remained the largest force in the September 2026 election and the centre-left secured a narrow parliamentary majority, but the party fell to 28.02%, down from 30.33% in 2022. It is another sign of a broader transformation visible across Europe: parties that once organised much of political life are finding it increasingly difficult to concentrate voters around them.
The Swedish result should not be read simply as another shift towards the political extremes. The Sweden Democrats (Sverigedemokraterna), which had grown steadily for years, also lost support, falling from 20.54% to 17.48%. At the same time, the Left Party (Vänsterpartiet) rose from 6.75% to 8.40%, while several smaller parties also gained ground.
What Sweden illustrates particularly well is therefore something more complicated: political systems are becoming increasingly fragmented, and being one of the traditional governing parties no longer guarantees the degree of electoral dominance it once did.
Sweden’s biggest party is much smaller than it used to be
For much of the twentieth century, Swedish politics was unusually closely associated with the Social Democrats. The party governed for long periods and helped shape institutions that became central to the Swedish welfare state.
That political dominance has gradually disappeared.
The final 2026 election result gave the Social Democrats 28.02% and 99 seats in the Riksdag. They were still comfortably Sweden’s largest party, but their vote share fell by more than two percentage points compared with the previous election.
As DR noted in its analysis of the election, the result fits into a much wider European debate about the declining strength of parties that historically alternated in government.
But the Swedish numbers also complicate that narrative. The Moderate Party (Moderaterna), Sweden’s main traditional centre-right party, actually increased slightly, from 19.10% to 19.85%. The Sweden Democrats lost around three percentage points. The Left Party, Greens, Christian Democrats, Centre Party and Liberals all gained support.
The story is therefore not simply one of voters abandoning the centre for the radical right. It is one of votes being distributed among a larger number of credible political alternatives.
The German example is more dramatic
Germany currently offers a more striking example of pressure on the parties that built the post-war political system.
For decades, German federal politics revolved primarily around the centre-right CDU/CSU and the centre-left SPD. Both remain in government today under Chancellor Friedrich Merz, but their combined dominance over the electorate has weakened considerably.
The trend is particularly visible in eastern Germany.
In the Saxony-Anhalt state election on 6 September, Alternative for Germany (AfD) received 43.8% of the vote, according to the results cited by DR. Two weeks later, the party also came first in Mecklenburg-Western Pomerania with around 37% in the initial projections, while the CDU recorded one of its weakest state-level performances.
AfD remains excluded from government by the refusal of the other major German parties to form coalitions with it. But its growth has changed the mathematics of German politics.
The consequence is paradoxical. As the traditional parties become weaker individually, they can become more dependent on each other to construct governing majorities. This can produce broad coalitions between parties that historically presented themselves as the principal alternatives to one another.
That may ensure institutional stability. It can also make it harder for those parties to persuade voters that elections offer clearly different governing choices.
Voting against the old parties can matter as much as voting for the new ones
This distinction is important when interpreting the rise of parties outside the traditional centre.
DR’s Brussels correspondent Ole Ryborg argues that part of their appeal comes precisely from the fact that they are not identified with the established parties that previously governed. A vote for them can therefore represent rejection as much as ideological alignment.
This does not mean that voters are indifferent to policy. Different parties attract different groups for different reasons, from immigration and security to welfare, climate policy, housing and the cost of living.
But electoral change is also driven by political identity. A party that has spent decades outside government can present itself as a challenge to an existing system in a way that a former governing party usually cannot.
Sweden offers an interesting example of what happens when that distinction begins to disappear. The Sweden Democrats entered the 2022-2026 parliamentary arrangement supporting Ulf Kristersson’s government. In 2026, their vote share fell for the first time in a Riksdag election since their breakthrough into parliament in 2010.
That does not prove that participation in government caused the decline. But it demonstrates the broader problem facing anti-establishment parties once they become part of the political establishment themselves.
France has already gone through a political realignment
The transformation has gone considerably further in France.
For decades, French presidential politics was dominated by the mainstream centre-left and centre-right. That structure largely collapsed with Emmanuel Macron’s victory in 2017.
Neither of the candidates representing the two political families that had previously dominated the presidency reached the second round that year. The same happened again in 2022, when Macron and Marine Le Pen contested the runoff for a second consecutive time.
In the 2022 first round, the candidate of the traditional centre-right received less than 5% of the vote, while the Socialist candidate received less than 2%.
France shows what can happen when the decline of established parties does not merely weaken the old system but replaces its principal competitors altogether.
The political space they once occupied has since been divided among Macron’s centrist movement, the National Rally on the right and a reorganised left.
UK shows that electoral systems can delay the consequences
The same pressures can produce very different parliamentary outcomes.
In the United Kingdom’s 2024 general election, Reform UK won 14.3% of the national vote, while the Greens received 6.7%. Together, however, they won only nine of the 650 seats in the House of Commons.
UK’s first-past-the-post electoral system continued to translate support heavily in favour of the two largest established parties.
Yet the vote itself showed increasing fragmentation. Labour won a large parliamentary majority with 33.7% of the vote, while the Conservatives fell to 23.7%.
This illustrates why measuring the decline of traditional parties only through the number of seats they control can be misleading. Electoral institutions can slow down the parliamentary effects of fragmentation without eliminating the underlying movement of voters.
Italy shows that yesterday’s challenger can become today’s establishment
Italy offers another variation.
Brothers of Italy was once a small opposition party outside the principal governing coalitions. Today, Giorgia Meloni has led the Italian government since October 2022, and in September 2026 her administration became the longest continuously serving government in the history of the Italian Republic.
That does not fit neatly into a narrative in which voters simply abandon governing parties for permanent outsiders.
Instead, it shows how quickly the distinction between established and insurgent parties can change. A political force can grow by campaigning against the parties traditionally associated with government and then itself become the central governing party.
The important transformation may therefore be less about a permanent victory of the political fringes than about a political market in which party loyalties are weaker and positions of dominance are less durable.
The crisis is about dominance, not necessarily democracy
There is also an important distinction between a crisis of traditional parties and a crisis of democratic participation.
Sweden’s election does not show an electorate withdrawing from politics. Turnout in the 2026 Riksdag election was 84.9%, slightly higher than in 2022.
Voters are still participating. They are simply distributing their votes differently.
This is one reason the Swedish election deserves attention beyond Sweden. The Social Democrats are still the country’s largest party. The Moderates remain a central political force. None of the historic parties has disappeared.
What has weakened is their ability to structure political competition almost by themselves.
That development can be seen in different forms in Sweden, Germany, France, Italy and UK. Its causes are not identical and neither are its beneficiaries. Sometimes the gains go to the radical right, sometimes to the left, sometimes to new centrist forces and sometimes to smaller established parties.
What connects these cases is a decline in the assumption that a small number of longstanding parties will naturally continue to organise government and opposition.
The Swedish election is therefore not evidence that Europe is moving uniformly in one ideological direction. It is evidence of something broader: the political systems built around a few dominant parties are becoming harder to sustain.
And as Germany is already showing, the more fragmented those systems become, the more difficult the next question becomes: not only who voters choose, but how those votes can still be assembled into governments.
