Albigensian Crusade
Mark Gregory Pegg (born 1963) is an Australian professor of medieval history, currently teaching in the United States at Washington University in St. Louis, Missouri. He specializes in scholarship of the Albigensian Crusade and the Inquisition, the history of heresy, and the history of holiness. He is author of "The Corruption of Angels: The Great Inquisition of 1245–1246" and "A Most Holy War: The Albigensian Crusade and the Battle for Christendom".