The United Nations began celebrating International Women’s Day in 1975.
That year was designated International Women’s Year by the United Nations, giving the March 8 observance a prominent place in the organization’s global work on women’s equality. The first UN World Conference on Women was also held in Mexico City from June 19 to July 2, 1975.
The 1975 conference produced a World Plan of Action and helped establish international mechanisms focused on women’s advancement, including the International Research and Training Institute for the Advancement of Women and the United Nations Development Fund for Women. The UN’s observance has continued annually, usually with a different theme.
A common mix-up is 1977. In that year, the UN General Assembly invited member states to designate a day for women’s rights and international peace according to their national traditions. That later resolution helped formalize wider participation, but the UN’s own celebration began in 1975.