There are a number of versions of the legend of St. Valentine; this is my favorite:
On February 14 around the year 278 A.D., Valentine, a holy priest in Rome in the days of Emperor Claudius II, was executed.
Under the rule of Claudius the Cruel, Rome was involved in many unpopular and bloody campaigns. The emperor had to maintain a strong army, but was having a difficult time getting soldiers to join his military leagues. Claudius believed that Roman men were unwilling to join the army because of their strong attachment to their wives and families.
To get rid of the problem, Claudius banned all marriages and engagements in Rome. Valentine, realizing the injustice of the decree, defied Claudius and continued to perform marriages for young lovers in secret.
When Valentine’s actions were discovered, Claudius ordered that he be put to death. Valentine was arrested and dragged before the Prefect of Rome, who condemned him to be beaten to death with clubs and to have his head cut off. The sentence was carried out on February 14, on or about the year 270.
Legend also has it that while in jail, St. Valentine left a farewell note for the jailer’s daughter, who had become his friend, and signed it “From Your Valentine.”
For his great service, Valentine was named a saint after his death.