German social democracy: repression and the birth of the welfare state

The German Social Democratic Party (SPD) originated in the merger of two workers' organizations at the Gotha Congress of 1875: the General German Workers' Association, founded by Ferdinand Lassalle in 1863, and the Marxist-oriented Social Democratic Workers' Party, led by August Bebel and Wilhelm Liebknecht. Marx harshly criticized the resulting compromise program in his Critique of the Gotha Programme (1875), and the party only formally adopted Marxism as its ideological basis at the Erfurt Congress of 1891, with the "Erfurt Programme" drafted principally by Karl Kautsky. The SPD grew rapidly in votes and membership, becoming the largest and most influential socialist party in Europe by around 1900, and in the 1912 Reichstag elections it became Germany's most-voted party, winning more than a third of the seats.