According to one legend, Valentine was a priest during the third century in Rome. When Emperor Claudius II decided that single men made better soldiers than those with wives and families, he outlawed marriage for young men. Valentine was not happy and he continued to perform marriages for young lovers in secret. When Valentine's actions were discovered, Claudius ordered that he be put to death.
According to another legend, Valentine actually sent the first 'valentine' greeting himself. While in prison, Valentine fell in love with a young girl. Before his death, he wrote her a letter, which he signed 'From your Valentine,' an expression that is still in use today.