This study explains the emergence of the Sicilian ma a in the XIX century as the product of the interaction between natural resource abundance and weak institutions. We advance the hypothesis that the ma a emerged after the collapse of the Bourbon Kingdom in a context characterized by a severe lack of state property-right enforcement in response to the rising demand for the protection of sulfur - Sicily's most valuable export commodity - whose demand in the in- ternational markets was soaring at the time. We test this hypothesis combining data on the early presence of the ma a and on the distribution of sulfur reserves across Sicilian municipalities and nd evidence of a positive and signi cant effect of sulphur availability on ma a's di usion. These results remain unchanged when including department xed-eects and various geographical and historical controls, when controlling for spatial correlation, and when comparing pairs of neighboring municipalities with and without sulfur.