The first known connection between love and birds appears in the British medieval poet Geoffrey Chaucer's work "Parliament of Fowls," in which the poet writes of birds choosing mates on Valentine's Day. Another 14th century poet, Otto de Granson, began the practice of writing Valentine's Day poetry but did not mention birds until one of his last poems.
The exact origins of Valentine's Day are difficult to determine, but there are indications that the holiday may have roots in both Roman and Norman tradition dating back to ancient Roman history and about 300 C.E. Between February 13 and 15 in ancient Rome, a holiday known as Lupercalia was celebrated. This was a rather brutal and violent festival during which men would slaughter animals, consume them and then use the animals' hides to whip women as part of a fertility ritual. The festival also included a matchmaking process in which men and women would be paired up based on a random lottery.
Each year in the United States, about 110 million roses are sold on February 14th, and international rose growers grow about 200 million flowers in preparation for the event. Valentine's Day is a major commercial holiday, and it is one of the biggest days of the year for the floral industry.