Sheila May Fitzpatrick (born June 4, 1941) is an Australian historian, whose main subjects are history of the Soviet Union and history of modern Russia, especially the Stalin era and the Great Purges, of which she proposes a "history from below", and is part of the "revisionist school" of Communist historiography. She has also critically reviewed the concept of totalitarianism and highlighted the differences between Nazi Germany and the Soviet Union in debates about comparison of Nazism and Stalinism. Fitzpatrick is professor at the Australian Catholic University (Melbourne), honorary professor at the University of Sydney, and Distinguished Service Professor Emerita at the University of Chicago. Prior to this, she was Bernadotte Everly Schmitt Distinguished Service Professor at the University of Chicago, where she taught Soviet history, for which she is considered a founder of the field.