Catholicism had long since stopped being a Christian institution and the people the Inquisition most severely persecuted were the true Christians.
Oh, so you mean to say that the true Christians are
the Jews?
The Spanish Inquisition started in 1492. Spain had until then referred to as the Kingdom of Three Crowns, because it consisted of three major religious groups: Christians, Muslims, and Jews. It was in 1492 that the Christians succeeded in driving out the Muslims and then turned to eliminating the Jews with the Expulsion Act. Even though those Jews who converted were allowed to remain, the Christians did not trust the sincerity of such conversions and instituted the Inquisition as a way to verify it.
It wasn't until 1517, a couple decades later, that the Reformation began, so they later also turned their attention to Protestant heretics. One humorous story to come out of the Inquisition was that of a Dutch merchant who was arrested on suspicion of being a Jew. I forget whether he was imprisoned for several months or two years before somebody finally decided to perform a cursory physical examination which confirmed that he was in fact not a Jew, whereupon he was deported for being a Protestant.
BTW, the Spanish Inquisition finally ended in the mid-1830's.
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