You can use the New Testament and Jesus own words/actions to criticise the [Spanish] Inquisition whilst you can't do the same with non-abrogated ayahs or by demonstrating the contrast with Mohammed's model of life.

There's documentary evidence, via Wikipedia, to support 1250 being sentenced to death by the Spanish Inquisition over a 200 year period. The monarchy in Spain established that Inquisition: the people were tried for things like witchcraft but also child rape, bestiality and such which are still consider serious crimes today - though seldom is capital punishment legally applied for those crimes now. Interestingly none of the motives mentioned in the Wiki' article is "spreading Christianity": indeed IIRC the Inquisitions apply to those "baptised" in to the Catholic church [albeit baptisms were often under duress of being expelled from Spain it seems].

Whatever atrocities can be pegged on Christians I don't see how that stops the Koran and Mohammed from being supporters of violent persecution however.