Step 1 : Introduction to the question "Which mobster is believed to behind the St. Valentine's Day Massacre?"
...The St. Valentine's Day Massacre remains the most notorious gangster killing of the Prohibition era. On Feb. 14, 1929, the St. Valentine's Day Massacre took place in a Chicago garage as seven rivals of Al Capone's gang were gunned down. The St. Valentine's Day Massacre, as it was known, was never officially linked to Capone, but he was generally considered to have been responsible for the murders. The incident resulted from the struggle to control organized crime in the city of Chicago during Prohibition. The story appeared on front pages around the country, making Al Capone a nationwide celebrity.
