1909
In accordance with a declaration by the Socialist Party of America, the first National Woman's Day (NWD) was observed across the United States on 28 February. Women continued to celebrate NWD on the last Sunday of February until 1913.

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1913-1914
On the eve of World War I campaigning for peace, Russian women observed their first International Women's Day on the last Sunday in February 1913. In 1913 following discussions, International Women's Day was transferred to 8 March and this day has remained the global date for International Women's Day ever since. In 1914 further women across Europe held rallies to campaign against the war and to express women's solidarity.