Benzion Netanyahu's book The Origins of the Inquisition in Fifteenth-Century Spain has been on my reading list for awhile now - not that that means I'll read it anytime soon. Maybe this article will move it up a few notches. Jason Epstein, who edited the book, sums up its thesis: for the first 509 years after the expulsion of the Jews of Spain in 1492, the version of the persecutors for its origin was accepted by all: they, meaning the Inquisition, had merely been trying to combat the phenomenon of descendants of Jews who had been forced to convert returning to Judaism. Not that the original forced conversions had been excusable, but at least there was a coherence to the policy. Once you're Christian you've got to live as one, and you're subordinate to the decrees of the Inquisition.
In 2001 Netanyahu published his magnum opus proving that it hadn't been like that at all. Most of the converts lived as Christians; freed from religious restrictions they had shot to the upper echelons of Spanish society, where their over-representation caused envy, and the envy caused racism. This was about 400 years before the invention of modern racism - or perhaps we need to re-write the books about racism and recognize it was there the whole time, directed at the usual suspects but masquerading as something else.
Interestingly, while the truth took five centuries to be uncovered, it took Netanyau 90 years to publish his research. There was quite a bit of patience going on in this story.