The idea that the war was avoidable became central among historians in the 1920s, 1930s and 1940s. Revisionist historians, led by James G. Randall (1881–1953) at the University of Illinois, Woodrow Wilson (1856–1924) at Princeton University and Avery Craven (1885–1980) at the University of Chicago, saw in the social and economic systems of the South no differences so fundamental as to require a war. Historian Mark Neely explains their position: