In many Western countries, the far left remains dominated by groups rooted in the radicalization of the 1960s. Most never became more than propaganda outfits of a few hundred members. The Socialist Party (SP) in the Netherlands is an exception. What started as just another left splinter developed into a mass party that seems posed to become the largest left of center force in the country.

The May 2014 municipal elections saw a dramatic change in the politics of the Dutch capital of Amsterdam: for the first time since its foundation in 1946, the social-democratic Labour Party (PvdA) disappeared from the municipal executive. Instead, two right-wing parties formed a coalition with the SP. So far, the Socialist Party’s attempts to overtake the PvdA nationally have failed, but it’s on the more established party’s heels.

The development is remarkable, all the more so because the Dutch left has historically been weak. The industrial working class, often the backbone of leftist parties in Europe, was relatively small in the Netherlands. And workers were long divided between Protestants and Catholics. Large parts of the disadvantaged Catholic working class were until the 1960s organized along religious lines. Social movements remain weak. Despite this, the SP has grown into the third largest party in the country.