In the 3rd century, St. Valentine was imprisoned for marrying soldiers and worshipping Christ. While imprisoned, he wrote a letter to a guard's daughter and signed it, "Your Valentine". He was executed shortly afterwards.
Over 11 centuries later, Valentine's Day was first associated with symbols of love and romance. Hand-made greetings, sweet candies, and love poems began to be shared with others around this time.
Nowadays, our love cards are manufactured, love poems are plagiarized off the internet, and chocolates, candies, and other gifts of affection have come to be an expectation on this day.