This one might be considered a bit ironic. According to legend, the oldest known Valentines was written by St. Valentine himself.
Valentine was imprisoned in Rome for secretly performing Christian marriages at a time when the emperor had banned them, believing unmarried soldiers made better fighters. While awaiting execution, Valentine befriended (or fell in love with, depending on the version) the jailer’s blind daughter. Through prayer, kindness, or divine intervention, her sight was restored. On the eve of his execution on February 14, 269 AD, Valentine is said to have written her a farewell note. He signed it: “From your Valentine.”
That simple closing, tender, personal, and intimate, became the phrase echoed centuries later on cards, letters, and love notes around the world.
Now the oldest known Valentine’s message still in existence is a poem written in 1415 by Charles, Duke of Orléans, to his wife, Bonne of Armagnac. Imprisoned in the Tower of London after the Battle of Agincourt, the Duke composed the French rondeau to his “very sweet Valentine”. The manuscript is held by the British Library in London.


