Paul IV, 1476–1559, pope (1555–59), a Neapolitan named Gian Pietro Carafa; successor of Marcellus II. First superior of the Theatines (see Cajetan, Saint), he was sternly ascetic. A leading reformer, he organized the Inquisition set up by Paul III. As pope, he labored to purify the clergy and abolish corruption and worldliness from the papal curia, thus promoting reform (see Counter Reformation). He repudiated the settlement between Mary I of England and Reginald Cardinal Pole, and he later declared Elizabeth I illegitimate and unfit to be queen. He was succeeded by Pius IV.