What remains of Florentine history may be briefly told.  Clement, now the undisputed arbiter of power and honour in the city, chose Alessandro de’ Medici to be prince.  Alessandro was created Duke of Civita di Penna, and married to a natural daughter of Charles V. Ippolito was made a cardinal.  Ippolito would have preferred a secular to a priestly kingdom; nor did he conceal his jealousy for his cousin.  Therefore Alessandro had him poisoned.  Alessandro in his turn was murdered by his kinsman, Lorenzino de’ Medici.  Lorenzino paid the usual penalty of tyrannicide some years later.  When Alessandro was killed in 1539, Clement had himself been dead five years.  Thus the whole posterity of Cosimo de’ Medici, with the exception of Catherine, Queen of France, was utterly extinguished.  But the Medici had struck root so firmly in the State, and had so remodelled it upon the type of tyranny, that the Florentines were no longer able to do without them.  The chiefs of the Ottimati selected Cosimo, the representative of Giovanni the Invincible, for their prince, and thus the line of the elder Lorenzo came at last to power.  This Cosimo was a boy of eighteen, fond of field-sports, and unused to party intrigues.  When Francesco Guicciardini offered him a privy purse of one hundred and twenty thousand ducats annually, together with the presidency of Florence, this wily politician hoped that he would rule the State through Cosimo, and realise at last that dream of the Ottimati, a Governo Stretto or di Pochi.  He was notably mistaken in his calculations.  The first days of Cosimo’s administration showed that he possessed the craft of his family and the vigour of his immediate progenitors, and that he meant to be sole master in Florence.  He it was who obtained the title of Grand Duke of Tuscany from the Pope—­a title confirmed by the Emperor, fortified by Austrian alliances, and transmitted through his heirs to the present century.

XXVIII

In this sketch of Florentine history, I have purposely omitted all details that did not bear upon the constitutional history of the republic, or on the growth of the Medici as despots; because I wanted to present a picture of the process whereby that family contrived to fasten itself upon the freest and most cultivated State in Italy.  This success the Medici owed mainly to their own obstinacy, and to the weakness of republican institutions in Florence.  Their power was founded upon wealth in the first instance, and upon the ingenuity with which they turned the favour of the proletariate to use.  It was confirmed by the mistakes and failures of their enemies, by Rinaldo degli Albizzi’s attack on Cosimo, by the conspiracy of Neroni and Pitti against Piero, and by Francesco de’ Pazzi’s attempt to assassinate Lorenzo.  It was still further strengthened by the Medicean sympathy for arts and letters—­a sympathy which placed both Cosimo and Lorenzo at the head of the Renaissance