The growth of socialist parties after 1871 was phenomenal. (See “Primary Source 23.5: Adelheid Popp, the Making of a Socialist.”) Neither Bismarck’s Anti-Socialist Laws nor his extensive social security system checked the growth of the Social Democratic Party, which espoused radical Marxism even though it sought reform through legal parliamentary politics. By 1912 the SPD had millions of followers — mostly people from the working classes — and was the largest party in the Reichstag. Socialist parties grew in other countries as well, though nowhere else with such success. In 1883 Russian exiles in Switzerland founded the Russian Social Democratic Party, and various socialist parties were unified in 1905 in the French Section of the Workers International. Belgium and Austria-Hungary also had strong socialist parties.

As the name of the French party suggests, Marxist socialist parties were eventually linked together in an international organization. Marx himself played an important role in founding the socialist International Working Men’s Association, also known as the First International. In the following years, he battled successfully to control the organization and used its annual meetings as a means of spreading his doctrines of socialist revolution. Marx enthusiastically endorsed the radical patriotism of the Paris Commune and its terrible struggle against the French state as a giant step toward socialist revolution. Marx’s fervent embrace of working-class violence frightened many of his early supporters, especially the more moderate British labor leaders. The First International collapsed.

Yet international proletarian solidarity remained an important objective for Marxists. In 1889, as the individual parties in different countries grew stronger, socialist leaders came together to form the Second International, which lasted until 1914. Though only a federation of national socialist parties, the International had a great psychological impact. The International had a permanent executive, and every three years delegates from the different parties met to interpret Marxist doctrines and plan coordinated action. May 1 (May Day) was declared an annual international one-day strike, a day of marches and demonstrations. Prosperous and conservative citizens feared the growing power of socialism and the Second International, but many others rejoiced in it.