Giovanni Pietro Caraffa
Became Pope in 1555 and died in 1559. Came from a humanist background having been educated by humanists. Also had helped to found the oratory of divine love, a society which had helped sow the first seeds of reform. However Paul IV was no spiritualist reformer, he was a hardliner compared to other reformers and felt there could be no compromise with Protestantism.
Reorganised the Roman Inquisition in 1542; it became an agency for suppressing heresy and discrediting Paul IV’s rivals. Took very harsh action against all his rivals, including members of the clergy, for example sending them to row in galleys.
Refused to reconvene the Council of Trent, feared conciliarism and felt he could reform on his own.
Wrote his own Papal Index, detailing all heretical writings of the time, the majority of which were Lutheran or Protestant.
Suspicious of the Jesuits and attempted to force changes on their constitution which were reversed after his death in 1559.
He opposed the treaty of Augsburg and also the Hapsburgs, the ruling family of the Holy Roman Empire, in Naples.
In general an overly zealous and unpredictable Pope.