Wikipedia:Selected anniversaries/March 18
March 18: Flag Day in Aruba (1976)
- 1229 - Sixth Crusade: Holy Roman Emperor Frederick II declared himself King of Jerusalem.
- 1438 - Albert II of Habsburg became King of the Romans in the Holy Roman Empire.
- 1921 - The Polish-Soviet War, which determined the borders between the Republic of Poland and Soviet Russia, formally concluded with the signing of the Peace of Riga.
- 1922 - Mahatma Gandhi was sentenced to six years in prison for civil disobedience.
- 1965 - Cosmonaut Aleksei Leonov donned a spacesuit and ventured outside the Voskhod 2 spacecraft (mission insignia shown), becoming the first person to walk in space.
Recent days: March 17 – March 16 – March 15
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