On this date in 1931, mafia “Boss of Bosses” Salvatore Maranzano was shot and stabbed to death in his office in Manhattan. Maranzano, whose reign as top man of the American Mafia lasted only a few months, became just a little too power hungry to suit his fellow mafiosi. Maranzano became aware of this resentment and began making arrangements to eliminate those who would oppose him. But one ambitious young gangster – Charles “Lucky” Luciano – beat Maranzano to the punch and had him rubbed out first, thereby living up to one of the golden rules of organized crime: Do unto others before they do unto you.
Encyclopedia Britannica – Salvatore Maranzano
Find a Grave – Salvatore Maranzano
Wikipedia – Salvatore Maranzano