Was Valentine’s Day inspired by a party, an execution, or a poem? Historians aren’t sure.
The earliest possible origin story of Valentine’s Day is the pagan holiday Lupercalia. Occurring for centuries in the middle of February, the holiday celebrates fertility. Men would strip naked and sacrifice a goat and dog. Young boys would then take strips of hide from the sacrificed animals and use it to whip young women, to promote fertility.
Lupercalia was popular and one of the few pagan holidays still celebrated 150 years after Christianity was legalized in the Roman Empire.
When Pope Gelasius came to power in the late fifth century he put an end to Lupercalia. Soon after, the Catholic church declared February 14 to be a day of feasts to celebrate the martyred Saint Valentine.