In 1894, Clara Zetkin took to the pages of the Social Democratic women’s magazine Die Gleichheit ( Equality ), which she had founded three years earlier, to polemicize against the mainstream of German feminism. “Bourgeois feminism and the movement of proletarian women,” Zetkin wrote, “are two fundamentally different social movements.”

According to Zetkin, bourgeois feminists pressed reforms, through a struggle between the sexes and against the men of their own class, without questioning the very existence of capitalism. By contrast, working women, through a struggle of class against class and in a joint fight with the men of their class, sought to transcend capitalism.

By 1900, women in the German Social Democratic Party (SPD) were holding biannual conferences immediately before the party congresses — conferences where all the burning issues of the proletarian women’s movement were discussed. This ideological and organizational strength turned the German Socialist working women’s movement into the backbone of the International Socialist Women Movement.

In 1907, the International Conference of Socialist Women convened in Stuttgart, Germany for its first gathering, proclaiming as its main demand “the right to universal female suffrage without qualifications of property, tax, education or any other kind of barrier which may hinder members of the working class from availing themselves of their political rights.” The struggle for the franchise, the delegates insisted, was to be carried out “not together with the women’s bourgeois movement, but in close co-operation with socialist parties.”

The invitation to the next International Conference of Socialist Women — held three years later in Copenhagen — exhibited the same adherence to the proletarian class struggle: “We urgently call on all the socialist parties and organizations of socialist women as well as on all the working women’s organizations standing on the foundation of the class struggle to send their delegates to this conference.”

They were in good company across the Atlantic. The previous year, socialist working women in the US had designated February 28 “Women’s Day” — “an event,” the Copenhagen conference reported the following year, “that has awakened the attention of our enemies.”

Following the example of their American comrades, the German delegate Luise Zietz proposed the proclamation of an “International Women’s Day,” to be celebrated annually. Zetkin seconded the proposal, along with one hundred female delegates from seventeen countries.

The Women’s Day resolution read:

In agreement with the class-conscious political and trade union organizations of the proletariat of their respective countries, socialist women of all nationalities have to organize a special Women’s Day (Frauentag), which must, above all, promote the propaganda of female suffrage. This demand must be discussed in connection with the whole woman’s question, according to the socialist conception.

For the delegates, supporting the “socialist conception” meant promoting not just female suffrage, but labor legislation for working women, social assistance for mothers and children, equal treatment of single mothers, provision of nurseries and kindergartens, distribution of free meals and free educational facilities in schools, and international solidarity.

Simply put, International Women’s Day was, from the very beginning, a Working Women’s Day. While its immediate objective was to win universal female suffrage, its aspirations were much grander: the overthrow of capitalism and the triumph of socialism, abolishing both the wage slavery of workers and the domestic slavery of women through the socialization of education and care work.