Well maybe that's one of the first "application", but it's a well know fact that Mafia's rise was fostered by the Italian unification.

Southern Italy was for the most part a feudal system controlled by a traditional aristocracy.

The unification prompted by one of the Northern Italian states meant the wiping out of the existing Southern Italian aristocracy.

Northern Italian bourgeoisie and aristocracy became the new ruling classes of the new unified Italy.

Although they tried to replace the Southern Italian aristocracy with a new class of bureaucracy, the traditional feudal structure of the South and the sudden void of power made it easier for an organization like Mafia to arise.