International Women's Day is sponsored worldwide by the United Nations. However, the UN did not originate this special celebration. The roots of this celebration goes back to the late 1800's and early 1900s. It grew from women's socialist movements and early women's trade union groups.
The first International Women's Day was held March 19, 1911. Women socialists and trade unions held an earlier Women's Day on the last Sunday in February, 1908. The event grew from there, and has been celebrated annually since. The focus is upon women workers, and advancing women's rights in the workforce, politics and society.