Inquisition.

Begun by the Dominicans under papal authority; resurrected by the Reyes Católicos who authorised the atrocities of Torquemada; the Spanish Inquisition lasted for about 350 years. It particularly made the conversos (Jews and Moslems) into targets. It was foul and vicious but was certainly overstated in the form of Leyenda Negra - principally by the Dutch. This was the selfsame technique used against the Spanish Conquistadores - often evil - but whose misdeeds were consistently overstated.

Goya.
For me the TV programme Inquisition tended to work more to the urban myths than to the records. It certainly revelled lasciviously in its descriptions of torture. This was, in effect, used considerably less than by mainstream courts. Trials ran into many tens of thousands but of those found guilty, between 0.1% & 1% were ever executed. The average numbers would appear to be a maximum of 15 deaths per year over the centuries and possibly as few as six. Most trial records still exist, although some were lost in the Napoleonic occupation, and I recall seeing a Spanish historian who, on TV, having studied the totals in great depth stated that some 2,000 perished. That figure is truly horrific BUT far short of the declarations of numbers listed in tens or even hundreds of thousands and some times - MILLIONS. Historical exaggerations have been legion. I suspect that this is part of the atheistic efforts to rewrite history so as to discredit Christianity in general. We have seen it with the Crusades, the Conquistadors - now it is The Inquisition's turn. Far be it from me to defend the Roman Church, but do let us have a little more honesty, please.