The story of the exposure of the Donation of Constantine is a familiar one. In the middle of the fifteenth century, it will be recalled, two different men, writing independently of each other in England and in Italy, demonstrated conclusively that the document was a forgery. Others had long suspected it and, on one occasion at least, carefully examined and rejected it. But it was left to Reginald Pecock and Lorenzo Valla to complete the criticism. When they were finished it was difficult, if not impossible, to continue to believe in either the document or the event. In this way, European historiography took a major step forward and the Renaissance relieved itself of one of the many legends that cluttered its understanding of the past.