After the departure of the emperor, Castruccio made himself master of Pisa, but the Florentines, by a treaty with Pistoia, withdrew her from obedience to him. Castruccio then besieged Pistoia, and persevered with so much vigor and resolution, that although the Florentines often attempted to relieve her, by attacking first his army and then his country, they were unable either by force or policy to remove him; so anxious was he to punish the Pistolesi and subdue the Florentines. At length the people of Pistoia were compelled to receive him for their sovereign; but this event, although greatly to his glory, proved but little to his advantage, for upon his return to Lucca he died. And as one event either of good or evil seldom comes alone, at Naples also died Charles duke of Calabria and lord of Florence, so that in a short time, beyond the expectation of their most sanguine hopes, the Florentines found themselves delivered from the domination of the one and the fear of the other. Being again free, they set about the reformation of the city, annulled all the old councils, and created two new ones, the one composed of 300 citizens from the class of the people, the other of 250 from the nobility and the people. The first was called the Council of the People, the other the Council of the Commune. CHAPTER VII The Emperor at Rome--The Florentines refuse to purchase Lucca, and repent of it--Enterprises of the Florentines--Conspiracy of the Bardi and the Frescobaldi--The conspiracy discovered and checked--Maffeo da Marradi appeases the tumult--Lucca is purchased by the Florentines and taken by the Pisans--The duke of Athens at Florence--The nobility determine to make him prince of the city.