We don't know much about Valentine. Indeed, there may well have been two 3rd century martyrs named Valentine — a Roman priest executed during the reign of the emperor Claudius and a bishop of Terni, also martyred in Rome. Nor do we know exactly when or how the holiday was transformed from a sacred into an amorous event. One of the most pervasive explanations is that Valentine's Day was linked to a pre-Christian Roman feast called Lupercalia celebrated on Feb. 15. On that day, Roman boys supposedly drew girls' names from an urn and the two "coupled" for the duration of the festival. But the association between Lupercalia and Valentine's Day has no firm foundation in fact.