Transnational feminism
In the "Oxford Handbook of Transnational Feminist Movements", Valentine Moghadam says that "women have worked together across borders since at least the mid-1800s. (55)" What is now called first wave feminism started in the early twentieth century in the West with a focus on women's suffrage. 
During World War II, the United States government gave women jobs because the war had caused a national shortage of labor. After the war ended, Irene Tinker says (oxford transnational), these jobs were taken away but women were no longer satisfied going back to their previous gender roles. Starting in the 1960s in the United States, second wave feminism emerged, defined by women's organization around "equal right to education, employment, and equal pay for equal work, and on sexual and reproductive rights."
Transnational feminism
The practice of transnational feminism networks, in which feminists started exchanging ideas and collaborating across nation-state borders, originated from the United Nations conferences in the 1970s. In 1975 the United Nations Decade of Women began with the United Nations declaration of an International Women's Year. This ushered in a decade of conferences that would continue to the present. Important events during this period included conferences in Mexico City (1975), Copenhagen (1980), Nairobi (1985), and Beijing in 1995.