Others, like Venice, resist the least encroachment of the Church, and stand aloof from Roman Christianity in jealous isolation.
The interests of one class are maritime, of another military, of a third industrial, of a fourth financial, of a fifth educational.

Amalfi, Pisa, Genoa, and Venice depend for power upon their fleets and colonies; the little cities of Romagna and the March supply the Captains of adventure with recruits; Florence and Lucca live by manufacture; Milan by banking; Bologna, Padua, Vicenza, owe their wealth to students attracted by their universities.

Foreign alliances or geographical affinities connect one center with the Empire of the East, a second with France, a third with Spain.

The North is overshadowed by Germany; the South is disquieted by Islam.

The types thus formed and thus discriminated are vital, and persist for centuries with the tenacity of physical growths.