International Women’s Day (IWD) was born out of women’s rights activism in the early 20th century. Its roots can be traced back to a 1908 demonstration for women in New York City—15,000 women marched through the streets advocating for better pay and shorter hours in addition to the right to vote.Then, in 1909, National Women’s Day was celebrated for the first time in the U.S. as an extension of these activists’ work. National Women’s Day was observed on the last Sunday of February until 1913, but the first official IWD was held in Austria, Denmark, Germany, and Switzerland on March 19, 1911. It was transferred to March 8 in 1913, and it was celebrated by the United Nations for the first time in 1975.