day (March 8) honouring the achievements of women and promoting women's rights. A national holiday in numerous countries, it has been sponsored by the United Nations (UN) since 1975.

International Women's Day (IWD) grew out of efforts in the early 20th century to promote women's rights, especially suffrage. In its campaign for female enfranchisement, the Socialist Party of America in 1909 held the first National Woman's Day, which was highlighted by mass meetings across the United States; the day was observed until 1913. Encouraged by German activist Clara Zetkin (Zetkin, Clara), the International Socialist Congress agreed in 1910 to create an international version of the U.S. holiday, and on March 19, 1911, the first IWD was held in Austria, Denmark, Germany, and Switzerland. More than one million people attended rallies marking the day. In the ensuing years the IWD was celebrated in additional countries and on varying dates. On March 8 (February 24, Old Style), 1917, women in Petrograd (St. Petersburg), Russia, marked the day by staging a strike to protest food shortages, poor living conditions, and World War I. This strike for “bread and peace” helped give rise to the Russian Revolution of 1917, which led to the abdication of Nicholas II on March 15 (March 2). In 1921 the date of the IWD was officially changed to March 8.