The holiday was probably named after St. Valentine, a Christian priest killed by the Roman emperor Claudius for preaching Christianity, although several priests with this name met similar fates.
One Valentine was killed Feb. 14, A.D. 270, for continuing to perform marriages after Claudius issued an order forbidding priests to do so. The emperor wanted young men to become soldiers rather than husbands and fathers.
Another legend connects the day to Lupercalia, an ancient Roman festival celebrated on Feb. 14. On that day, young women would put slips of paper with their names into a bowl. Then young men would draw out the names of the girl who'd accompany him to parties and dances in the coming year. Christians adopted the pagan celebration as a day to honor a saint.
During the Middle Ages, Europeans believed birds chose their mates on Feb. 14. Following the birds' example. The French and English threw parties on Valentine's Day following customs similar to Lupercalia's. As more people learned to read and write, they began sending poems and cards to their sweethearts. The Valentine card industry was born when companies started making special valentines for the less creative.
Richard Cadbury designed the first "chocolate box" in 1868 when he decorated a candy box with a painting of his young daughter and her kitten. He also invented the first heart-shaped Valentine's Day candy box that same year.