The first IWD was held on 19 March 1911 in Germany, Austria, Denmark and further European countries. German women selected this date because in 1848, the Prussian king had promised the vote for women. Subsequently, over one million leaflets calling for action on the right to vote were distributed throughout Germany before IWD in 1911. Now IWD is always celebrated on 8 March and is an occasion marked by women's groups around the world. This date is also commemorated at the United Nations and is designated in many countries as a national holiday. Women in every country, often divided by ethnic, linguistic, cultural, economic and political differences, come together to celebrate this important date that represents equality, justice, peace and development.

See http://www.internationalwomensday.com/