15. European parties:
The party system of the European Parliament (EP) has been dominated by the two main European party families: centre-right conservatives and Christian democrats, on the one hand, and centre-left social democrats on the other, which controlled the majority of the seats until the 2019 elections. In the early 1950s, members of the European Parliament (MEPs) decided to form party-political groups, instead of national blocs, to counterbalance the dominance of national interests in the Council. Over the decades, the shape of the EP party system has become more stable, and traditional levels of group cohesion and coalition formation have not really been affected by the rise of populism and the increasing politicization of European integration. National parties remain influential within party groups, not least through their control of candidate selection. Outside of the Parliament, Europarties—parties operating at the European level—influence both the broader development of integration and the choice of the Commission president.