The Pursuit of the Millennium
The Pursuit of the Millennium: Revolutionary Millenarians and Mystical Anarchists of the Middle Ages (1957, revised and expanded in 1970) is Norman Cohn's study of millenarian cult movements. Covering a wide span of time, Cohn's book discusses topics such as anti-Semitism and the Crusades, in addition to such sects as the Brethren of the Free Spirit, flagellants, the Anabaptists, and the Ranters.
Source: Wikipedia — The Pursuit of the Millennium (CC BY-SA 4.0)