Are not just myths, m2w. I didn't mean these in particular as these are indeed stories. But feudal Italy has always been ran by thugs. You could argue that all of feudal europes noble class and knighthood were just thugs extorting the serfs. But in Italy it stuck. That's why the story is the rejected knights of sicily who settled in Calabria.
You had families like Medici family from Florence, one of first bankers in Europe , they were insanely powerful,ordered deaths of many people , they operated like todays mafia , but we can't call them organized crime , it was not an organization with rituals,ranks and so on as m2w said
