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The day was originally called
Tango no Sekku (端午の節句[sup]
?[/sup]), and was celebrated on the 5th day of the 5th moon in the
lunar calendar or
Chinese calendar. After Japan switched to the
Gregorian calendar, the date was moved to May 5.[sup]
[1][/sup] It was originally exclusively male celebrating
boys and recognizing fathers, but has since been changed to include both boys and girls, as well as recognizing mothers along with fathers.
Until recently,
Tango no Sekku was known as
Boys' Day (also known as
Feast of Banners) while Girls' Day (
Hinamatsuri) was celebrated on March 3. In 1948, the government decreed this day to be a national holiday to celebrate the happiness of all children and to express gratitude toward mothers. It was renamed
Kodomo no Hi.