In the twenty years between 1512 and 1532 Florentines incessantly debated the fate of their republic only to see it finally decided by external power. Three times, in 1433, 1494, and 1527, the Medici were exiled, and three times they returned: recalled in 1434 by friends in the city; restored in 1512 by both internal allies and a foreign army; but imposed in 1530 on an unwilling and defeated city after a year-long siege by the armies of Emperor Charles V, who two years later terminated Florence’s long republican history and instituted the principate. This time the Medici returned to stay and to govern in relative stability until they died a natural death 200 years later. Behind so improbable a conclusion to the stormy relationship between Florence and its most famous family lay the events of 1527-30, which traumatized both ottimati and popolo: the radicalization of the republic during the siege terrified the ottimati, and the republic’s isolation, abandonment, and crushing defeat devastated the popolo. In the aftermath of the siege and savage repression by emperor, Medici pope, and leading ottimati, even the kind of brief collaboration between elite and popolo that expelled the Medici in 1494 and 1527 was no longer possible. Brutalized by the ottimati, the popolo never again trusted them and refused to join the abortive revolts (in 1537, 1554, 1559, and 1575) of those few ottimati who rejected the inevitable. And now it was indeed inevitable because most ottimati, frightened by the popolo’s radicalized republicanism, finally accepted the principate and, in the process, the final metamorphosis of their own class into a subservient courtly aristocracy.