Salvatore Maranzano, nicknamed Little Caesar, was an Italian-American mobster from the town of Castellammare del Golfo, Sicily, and an early Cosa Nostra boss who led what later would become the Bonanno crime family in New York City. He instigated the Castellammarese War in 1930 to seize control of the American Mafia, winning the war after the murder of rival faction head Joe Masseria in April 1931. He then briefly became the Mafia's capo di tutti capi and formed the Five Families in New York City, but was murdered on September 10, 1931, on the orders of Charles "Lucky" Luciano, who established The Commission, in which families shared power to prevent future turf wars.

Castellammare del Golfo is a town and municipality in the Trapani Province of Sicily. The name can be translated as "Sea Fortress on the Gulf", stemming from the medieval fortress in the harbor. The nearby body of water conversely takes its name from the town, and is known as Gulf of Castellammare.