Examining the history of the `Abbasid caliphate between 809 and 833, a period that began in civil war between the two sons of the just-deceased Harun al-Rashid and ended with the reign of one of the brothers, al-Ma'mun, on Baghdad's throne, Yücesoy (history, Saint Louis U.) focuses on the role of Muslim and non-Muslim messianic and apocalyptic beliefs in shaping political behavior in the caliphate. He explores prophecies as discourse, as evidence of a political mentality, and as normative moral and ideological prescription in `Abbasid history and then turns to the messianic and apocalyptic dimensions of the civil war, particularly al-Ma'mun's efforts to project the image of a messianic contender and ruler in response to apocalyptic anxieties during the war. He then examines the foreign and domestic policies of al-Ma'mun's reign, arguing that his vigorous politics demonstrate a constructive engagement with messianic beliefs in imperial politics. Annotation ©2009 Book News, Inc., Portland, OR (booknews.com)