Although the day wasn't officially recognized until 1977 by the United Nations, the history of the celebration can be traced back to the early 20th century, thanks to labor movements across North America and Europe.
The first International Women’s Day occurred on March 19 in 1911. The inaugural event, which included rallies and organized meetings, was a big success in countries such as Austria, Denmark, Germany and Switzerland. The March 19 date was chosen because it commemorated the day that the Prussian king promised to introduce votes for women in 1848. The promise gave hope for equality but it was a promise that he failed to keep. The International Women’s Day date was moved to March 8 in 1913.
Members of the women's movement in Russia during World War I celebrated the first International Women's Day on March 8, 1913 to peacefully protest the war. A year later, women across Europe held rallies in solidarity on that same date.
Following World War II, countries from all continents began using March 8 as a marker for advocating women's equality.
The UN drew global attention to women's concerns in 1975 by calling for an International Women's Year.
More than a century later, numerous events and marches still take place on that day to celebrate the achievements of women and to take action.
The United Nations is focusing this year on gender equality and human rights for all women and girls. The theme of the commemoration is: "I am Generation Equality: Realizing Women's Rights.
"Much progress has been made to protect and promote women’s rights in recent times. However, nowhere in the world can women claim to have all the same rights and opportunities as men, according to the UN. The majority of the world's 1.3 billion absolute poor are women. On average, women receive between 30 and 40 percent less pay than men earn for the same work. Women also continue to be victims of violence, with rape and domestic violence listed as significant causes of disability and death among women worldwide.