At the time when Catherine was born, history, if related from the point of view of honesty, would seem an impossible romance. Charles V., while forced to uphold the Catholic Church against the attacks of Luther, who by threatening the tiara threatened his throne, allowed Rome to be besieged, and kept Pope Clement VII. in prison. This same Pope, who had no more bitter foe than Charles V., cringed to him that he might place Alessandro de' Medici at Florence, and the Emperor gave his daughter in marriage to the bastard Duke. No sooner was he firmly settled there than Alessandro, in concert with the Pope, attempted to injure Charles V. by an alliance, through Catherine de' Medici, with Francis I., and both promised to assist the French king to conquer Italy. Lorenzino de' Medici became Alessandro's boon companion, and pandered to him to get an opportunity of killing him; and Filippo Strozzi, one of the loftiest spirits of that age, regarded this murder with such high esteem that he vowed that each of his sons should marry one of the assassin's daughters. The sons religiously fulfilled the father's pledge at a time when each of them, under Catherine's protection, could have made a splendid alliance; for one was Doria's rival, and the other Marshal of France. Cosmo de' Medici, Alessandro's successor, avenged the death of the Tyrant with great cruelty, and persistently for twelve years, during which his hatred never flagged against the people who had, after all, placed him in power. He was eighteen years of age when he succeeded to the government; his first act was to annul the rights of Alessandro's legitimate sons, at the time when he was avenging Alessandro! Charles V. confirmed the dispossession of his grandson, and recognized Cosmo instead of Alessandro's son. Cosmo, raised to the throne by Cardinal Cibo, at once sent the prelate into exile. Then Cardinal Cibo accused his creature, Cosmo, the first Grand Duke, of having tried to poison Alessandro's son. The Grand Duke, as jealous of his authority as Charles V. was of his, abdicated, like the Emperor, in favor of his son Francesco, after ordering the death of Don Garcias, his other son, in revenge for that of Cardinal Giovanni de' Medici, whom Garcias had assassinated. Cosmo I. and his son Francesco, who ought to have been devoted, soul and body, to the Royal House of France, the only power able to lend them support, were the humble servants of Charles V. and Philip II., and consequently the secret, perfidious, and cowardly foes of Catherine de' Medici, one of the glories of their race.