As per one legend, the holiday has originated from the ancient Roman festival of Lupercalis/Lupercalia, a fertility celebration that used to observed annually on February 15. But the rise of Christianity in Europe saw many pagan holidays being renamed for and dedicated to the early Christian martyrs. Lupercalia was no exception. In 496 AD, Pope Gelasius turned Lupercalia into a Christian feast day and set its observance a day earlier, on February 14.
When you think of Valentine’s Day you probably think of flowers, chocolates, and notes sealed with a kiss—not whipping women with dead animals or martyrdom.
The festival, which celebrated the coming of spring, included fertility rites and the pairing off of women with men by lottery. At the end of the 5th century, Pope Gelasius I replaced Lupercalia with St. Valentine’s Day. It came to be celebrated as a day of romance from about the 14th century.
It is not exactly known why the 14th of February is known as Valentine’s Day or if the noble Valentine really had any relation to this day. The history of Valentine’s Day is impossible to be obtained from any archive and the veil of centuries gone by has made the origin behind this day more difficult to trace.