The Corleonesi is the name given to a faction within the Sicilian Mafia that dominated Cosa Nostra in the 1980s and the 1990s. It was called the Corleonesi because its most important leaders came from the town Corleone, first Luciano Leggio and later Totò Riina, Bernardo Provenzano and Leoluca Bagarella, Riina’s brother-in-law. The Corleonesi coalition managed to take over the Sicilian Mafia Commission and imposed a quasi-dictatorship over Cosa Nostra, waging war against rival factions (also known as the Second Mafia War) from 1978-1983. The more established Mafia factions in the city of Palermo grossly underestimated the mafiosi from Corleone and often referred to the Corleonesi as i viddani - "the peasants".
Corleonesi affiliates were not restricted to mafiosi of Corleone. The Corleone Mafia bosses initiated “men of honour”, not necessarily from Corleone, whose status was kept hidden from the other members of the Corleone cosca and other Mafia Families. Members of other Mafia Families who sided with Riina and Provenzano were called Corleonesi as well, forming a coalition that dominated the Mafia in the 1980s and 1990s, that can be considered as a kind of parallel Cosa Nostra.