In St Valentine's life, first of all, he was in Rome during a time when the emperor had a strange view on marriage for young men. Valentine, being a man of love and faith, started to secretly marry these young men. This act of his led to his arrest. While in prison, he had an interaction with the jailer's daughter. And his death on February 14th is a very important event. All these events together make his life story so interesting and his name synonymous with love.
The main events include his role as a priest in Rome. Then there's his secret performance of marriage ceremonies for young lovers against the emperor's wishes. He was also imprisoned, and during that time, there are stories of him healing the jailer's daughter. And finally, his execution which led to him becoming a symbol of love.
One key event was his defiance of the emperor's ban on young men's marriage. Another was his subsequent arrest. And of course, his execution on February 14th.