In what way were the Italian city-states geographically, socially, and politically predisposed to benefit from the economic changes occurring in Europe following the Crusades?

The most important effect of the Crusades was economic. The Italian cities prospered from the transport of Crusaders and replaced Byzantines and Muslims as merchant-traders in the Mediterranean. Trade passed through Italian hands to Western Europe at a handsome profit. This commercial power became the economic base of the Italian Renaissance.