St. Valentine: How a beheaded martyr became the patron saint of …

The St. Valentine celebrated today may have been two different people. One account holds that St. Valentine was a priest in Rome, and the other says he was a bishop of Interamna (modern-day Terni). Both of these men were persecuted and ultimately killed for their faith, and buried somewhere along the Flaminian Way.

https://ewtn.co.uk/article-st-valentine-how-a-beheaded-martyr-became-the-patron-saint-of-romantic-love/