The first of these was termed the _Monte de' Nobili_; for Siena, like all Italian free burghs, had originally been controlled by certain noble families, who formed the people and excluded the other citizens from offices of state.

In course of time the plebeians acquired wealth, and the nobles split into parties among themselves.

To such a pitch were the quarrels of these nobles carried, that at last they found it impossible to conduct the government, and agreed to relinquish it for a season to nine plebeian families chosen from among the richest and most influential.

This gave rise to the _Monte de' Nove_, who were supposed to hold the city in commission for the nobles, while the latter devoted themselves to the prosecution of their private animosities.

Weakened by feuds, the patricians fell a prey to their own creatures, the _Monte de' Nove_, who in their turn ruled Siena like oligarchs, refusing to give up the power which had been intrusted to them.