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."
The Feminists
The group was founded in 1968 as a split from the New York City chapter of National Organization for Women (NOW) by members who felt NOW was not radical enough. It was originally called the after the date that it was founded, but soon changed its name to The Feminists. Ti-Grace Atkinson was the group's central figure and informal leader until she left the group in 1971; other prominent members included Anne Koedt (who left in 1969 to co-found New York Radical Feminists), Sheila Michaels, Barbara Mehrhof, Pamela Kearon, and Sheila Cronan.