For more than 100 years, March 8th has marked what has come to be known as International Women's Day in countries around the world. While its purpose differs from place to place—in some countries it's a day of protest, in others it's a way to celebrate the accomplishments of women and promote gender equality—the holiday is more than just a simple hashtag. Ahead of this year's celebration, let's take a moment to explore the day’s origins and traditions.

1. International Women's Day originated more than 100 years ago.

German Communist leader Clara Zetkin (1857 - 1933), known as Red Clara, and a companion
German Communist leader Clara Zetkin with a companion.
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On February 28, 1909, the now-dissolved Socialist Party of America organized the first National Woman's Day, which took place on the last Sunday in February. In 1910, Clara Zetkin—the leader of Germany’s 'Women's Office' for the Social Democratic Party—proposed the idea of a global International Women's Day, so that people around the world could celebrate at the same time. On March 19, 1911, the first International Women's Day was held; more than 1 million people in Germany, Switzerland, Austria, and Denmark took part.

2. The celebration got women the vote in Russia.

Women marching during the Russian Revolution in 1917, demanding the right to vote.
Women marching during the Russian Revolution in 1917, demanding the right to vote.
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In 1917, women in Russia honored the day by beginning a strike for "bread and peace" as a way to protest World War I and advocate for gender parity. Czar Nicholas II, the country's leader at the time, was not impressed and instructed General Khabalov of the Petrograd Military District to put an end to the protests—and to shoot any woman who refused to stand down. But the women wouldn't be intimidated and continued their protests, which led the Czar to abdicate just days later. The provisional government then granted women in Russia the right to vote.

3. The United Nations officially adopted International Women's Day in 1975.

International Women's Day demonstrations in Italy
International Women's Day demonstrations in Italy.
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In 1975, the United Nations—which had dubbed the year International Women's Year—celebrated International Women's Day on March 8th for the first time. Since then, the UN has become the primary sponsor of the annual event and has encouraged even more countries around the world to embrace the holiday and its goal of celebrating "acts of courage and determination by ordinary women who have played an extraordinary role in the history of their countries and communities."

4. International Women's Day is an official holiday in dozens of countries.

Afghan women attend a ceremony to mark International Women's Day, on March 8, 2010 in Herat, Afghanistan
Women attend a ceremony to mark International Women's Day in Herat, Afghanistan.
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International Women's Day is a day of celebration around the world, and an official holiday in dozens of countries. Afghanistan, Cuba, Vietnam, Uganda, Mongolia, Georgia, Laos, Cambodia, Armenia, Belarus, Montenegro, Russia, and Ukraine are just some of the places where March 8th is recognized as an official holiday.

5. International Women's Day is a combined celebration with Mother's Day in several places.

Celebrating International Women's Day with flowers and gifts
Celebrating International Women's Day with flowers and gifts.
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In the same way that Mother's Day doubles as a sort of women's appreciation day, the two holidays are combined in some countries, including Serbia, Albania, Macedonia, and Uzbekistan. On this day, children present their mothers and grandmothers with small gifts and tokens of love and appreciation.

6. Each year's International Women's Day festivities have an official theme.

International Women's Day March 8th
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In 1996, the UN created a theme for that year's International Women's Day: Celebrating the Past, Planning for the Future. In 1997, it was "Women at the Peace Table," then "Women and Human Rights" in 1998. They've continued this themed tradition in the years since; for 2020, it's "Let's all be each for equal" or #EachforEqual.