Valentine's Day is believed to have originated during the time of the Roman Empire. In ancient Rome, February 14 was a holiday to honour Juno, the Queen of the Roman gods and goddesses. The Romans also knew her as the goddess of women and marriage.

VALENTINE’S DAY is believed to have originated during the time of the Roman Empire. In ancient Rome, February 14 was a holiday to honour Juno -- the Queen of the Roman gods and goddesses. The Romans also knew her as the goddess of women and marriage.

 
The following day, February 15, began the Feast of Lupercalia in Rome with a pagan.
 

The pastors of the early Christian Church in Rome endeavoured to do away with the pagan element in these feasts by substituting the names of saints for those of maidens.
 
And, as the Lupercalia began about the middle of February, the pastors appear to have chosen Saint Valentine’s Day for the celebration of this new feast. So it seems that the custom of young men choosing maidens for valentines, or saints as patrons for the coming years arose in this way.
 
By the middle ages, St Valentine became the patron saint of love and lovers in England and France.
 
In 498 AD, when Pope Gelasius decided to put an end to pagan celebration of Feast of Lupercalia, he declared that 14th February be celebrated as St Valentine’s Day.
 
Some scholars however, say, romance was linked with Valentine’s Day because of the popular belief in England and France during the middle ages that birds began to start looking for their mates from February 14.