In the 12th Century, Pope Innocent the 3rd set off the Spanish Inquisition by declaring, "Anyone who attempts to construe a personal view of god which conflicts with Church dogma must be burned without pity."
Now there is a lovely fellow. Imagine taking confession with Pope"Innocent? Now there is a fitting name??
Compared to some of his predecessors Pope Innocent the 3rd was relatively sane.
Pope Stephen VI exhumed his predecessor Pope Formosus, had the body dressed up in papal robes and then put it on trial, with an unfortunate Deacon forced to sit behind the corpse operating its jaw and speaking for it.
Needless to say the former pope was found guilty, retroactively stripped of his papacy and buried again in a paupers grave.
Pope John XII was murdered by the husband of a woman from whom he was taking confession, understandable as both were strangely naked at the time, were in her bed and drew attention to themselves with loud appeals to the lord.
Pope Benedict IX was the youngest pope ever and was quite an astute business man having sold his papacy not once but three times.
Worst of all was Pope Urban VI who having uncovered a seditious plot against him, sent the guilty parties to be publicly tortured. However when the screaming of the condemned was not loud enough, he had the tortures arrested and tortured to death along side their former victims, by specially imported torturers from the king of Italy's own dungeons. Presumably these specialists elicited screaming loud enough to please the ears of his holiness.
Savage Animals since 7th century crusaders leading to 12th century inquisitors. Pope Innocent III was anything but. [churchandstate.org.uk]