The warfare of extermination carried on by the Popes against the house of Hohenstauffen was no proof of their partiality for the cause of freedom.
They dreaded the reality of a kingdom that should base itself on Italy and be the rival of their own authority.

Therefore they espoused the cause of the free burghs against Frederick, and when the North was devastated by his Vicars, they preached a crusade against Ezzelino da Romano.

In the convulsions that shook Italy from North to South the parties of Guelf and Ghibelline took shape, and acquired an ineradicable force.

All the previous humors and discords of the nation were absorbed by them.

The Guelf party meant the burghers of the consular Communes, the men of industry and commerce, the upholders of civil liberty, the friends of democratic expansion.