May 6, 1527: An army of barbarians who had been sent—but were no longer controlled—by Emperor Charles V sacks Rome. Many Protestants interpreted the attack as a divine rebuke, and some Catholics agreed: "We who should have been the salt of the earth decayed until we were good for nothing," wrote Cardinal Cajetan, Luther's adversary. "Everyone is convinced that all this has happened as a judgment of God on the great tyranny and disorders of the papal court.

May 6, 1638: Dutch theologian ...