Why do we celebrate Valentine's Day and who was Saint Valentine?

Each Valentine's Day, millions of Americans gift their partners or loved ones with flowers, cards or candy as a token of their affections on Feb. 14. But while some see it as a commercialized "Hallmark holiday," the occasion actually has ancient roots in Roman history and connections to Saint Valentine.

Valentine's Day is the perfect chance to ask someone on a date or to cement a long-lasting commitment to a partner. It could also be a great day to set aside time for yourself or spend a meal with family and friends.

Some other Americans, though, rail against a day they feel is an over-commercialization of love, or the holiday might make them feel lonely if they aren't in a pair.