To systematically refute Dunning's interpretation, Stampp amassed a trove of secondary sources. He was criticized for not employing more primary material. Stampp's rejoinder was seen by some historians as a pro-Northern rationalization: though he clearly admitted that the North walked out on Reconstruction while it was nowhere near completion, he went on to claim that in light of the passage of the 14th and 15th amendments, Reconstruction was a success; he deemed it "the last great crusade of nineteenth-century romantic reformers." But for an equal number of other historians, Stampp's appraisal rang as eminently "temperate, judicious and fair-minded."