The St. Valentines Day Massacre was the deadly result of a power struggle for control of Chicago's organized crime. The battle between Bugs Moran and Al Capone finally came to a head on February 14, 1929.
Al Capone made it be known that he was at his winter home in Florida, during the actual shooting. Although 1000 miles away, insiders knew he was responsible for the massacre that occured on Feb. 14, 1928.
Valentines Day was for Saint Valentine. Most stores just wanted to make it a holiday so they could get money by selling candy so they started the holiday Valentines day on the feast day of Saint Valentine