Valentine’s Day is famously known as a day to celebrate those you love. It’s a day where most exchange gifts of flowers, chocolate and/or sappy cards. However, what most people don’t know is that Valentine’s Day was not always this sweet and that the man it is named after made the ultimate sacrifice.

The holiday as we know it has a lot of religious background to it. It was formed back in the fifth century when Pope Gelasius combined two days to expel pagan rituals. Those two days being Lupercalia and the feast day of Saint Valentine.

Lupercalia was a very ancient feast that Roman’s celebrated, held on Feb. 15. During this celebration, men would sacrifice a goat and a dog and then whip women with the hides of the animals they had just slain. This celebration included a matchmaking lottery where a man and a woman would be coupled up for the remainder of the celebration or longer if the match fit. This entire feast was done in hope of averting evil spirits and purifying the city, which they believed would release health and fertility.

Under Emperor Claudius II, two men were executed on Feb. 14 of different years during the third century. Both of these men were named Valentine. According to catholic.org, not too much is known about Saint Valentine, but it is highly agreed that he was martyred and buried on the Via Flaminia north of Rome. Common stories regarding him are that he was imprisoned for marrying Christian couples and aiding Christians being persecuted by Claudius in Rome. Another story was that he was secretly marrying couples so that husbands wouldn’t have to go to war. Another one said that he refused to sacrifice to the pagan gods, was imprisoned and during his time in jail healed the jailers blind daughter. On the day of his execution he left the girl a note and signed it “your valentine.” Saint Valentine is known as the patron saint of, among other things, affianced couples, engaged couples, happy marriages, love and lovers.

Valentine’s Day did not have the sweet connotations that we know of today for a long period of time. In fact, it wasn’t until 1375, when Chaucer linked a tradition of courtly love with the celebration of Saint Valentine’s feast day. In his poem, “Parliament of Foules,” Chaucer wrote, “For this was sent on Seynt Valentyne’s day / Whan every foul cometh ther to choose his mate,” which essentially is saying that on Feb. 14, birds and humans come together to find a mate.

After that, Saint Valentine’s day was linked to love and celebrating love. In the 19th century, the industrial revolution started the tradition of factory-made cards. In 1913, Hallmark Cards began to mass produce Valentine’s Day cards and with that began the consumer based holiday we know today.