Putnam argued that the different levels of social capital between the North and the South of Italy originated in the Middle Ages. In the North of Italy, the existence of a dense network of medieval towns gave rise to horizontal ties and collective action. Conversely, in the South of Italy, the authoritarian Norman rule generated hierarchical relationships and the absence of collective action. This article proposes an alternative explanation for the lack of social capital in the South of Italy using a comparative perspective. The analysis is undertaken in two steps: 1) testing the socio-economic determinants of social capital in 85 European regions; 2) performing a comparative historical analysis between deviant – that is, South of Italy and Wallonia – and regular – that is, North East of Italy and Flanders – cases. These cases are selected by looking at the residual of the regression model. The results suggest that medieval history does not explain the lack of social capital in the South of Italy. On the contrary, the historical legacy mitigates the negative effect of inequitable income distribution, low labour market participation and weak national cohesion on social capital.