The things that made Capone so famous was that he ran one of the most infamous mobs during the 1920's. Capone was most likely known for prohibition, or alcohol trade. Another thing that he was famous for is the St. Valentines Day Massacre. This was the murder of rival gang's that traded alcohol. Capone lined up these gangs and killed them. There was even one instance where a doctor and reporter were killed just for witnessing the murder.