Harry Elmer Barnes (1889–1968) was a pioneer of historical revisionism, meaning the use of historical scholarship to challenge and refute the narratives of history promulgated by the state and the political class, or as Barnes himself termed it, "court history." Long regarded as a progressive intellectual leader of the American Left, Barnes became associated with the Old Right for his opposition to the New Deal and to American entry into World War II. His work has had a profound influence on New Left historians such as William Appleman Williams and Gabriel Kolko, as well as on the historical writings of Murray Rothbard and other libertarians.
See Murray Rothbard's editorial in Left & Right, "Harry Elmer Barnes, RIP."
Ludwig von Mises: "Marx and Engels never tried to refute their opponents with argument. They insulted, ridiculed, derided, slandered, and traduced them, and in the use of these methods their followers are not less expert. Their polemic is directed never against the argument of the opponent, but always against his person." - Socialism