For this reason I did a little reading up on Valentine's Day.
I had known for some time the holiday started with an actual person named St. Valentine but I didn't know much more than that. Apparently in the days of ancient Rome sometime in mid February, as a commemoration of boys passing to man hood, the boys would draw a girls name from a box. For the next year these two would be "companions" (trying to keep it clean). The pagan god Lupercus was associated with this ceremony.
Pope Gelasius was not happy with this practice and made a few changes. Instead of drawing names for "companions", now both young men and women would draw the name of a Saint. For the remainder of the year they were to conduct themselves as the saint would have. In addition to the customary changes the Pope also wanted to change from a pagan god to a patron saint.
They decided upon St. Valentine who was beheaded by the Roman Emperor Claudius in 270 AD for secretly marrying Roman soldiers. During Claduius' reign he decided unmarried men made much better soldiers and outlawed marriage. While St. Valentine was in jail he fell in love with the jailors blind daughter. Through his undying love and faith he miraculously healed the daughter. Before he was taken from the jail to be served his sentence he left her a note signed, "from your Valentine".
The mid-February holiday continued but changed again. Now it was customary for Roman men to give women they admired hand written messages, often containing Valentine's name.
Information for this article was taken from this article.
The Valentine pictured is from c. 1920 and is approximately 2 inches tall. (Photo taken from Wikipedia).