The Decline of Iranshahr: Irrigation and Environments in the History of the Middle East, 500 B.C. to A.D. 1500.

• Author: Daniel, Elton L.

Most modern accounts of Middle Eastern history are constructed around the rise and fall of dynasties or states. The paradigm they employ, implicitly or explicitly, for the history of the Islamic Middle East, in particular, is familiar enough. There is the decisive watershed of the Arab conquests and the rise of Islam, followed by the golden age of the high caliphate, and then by a period of political fragmentation, decadence, and disruption of sedentary civilization culminating in the catastrophe of the Mongol invasions. This innovative and stimulating book by Peter Christensen, clearly written from the perspective of a modern "macro historian" rather than the traditional Orientalist, challenges virtually every comfortable convention of this received wisdom.

At first glance, the title of the book may seem somewhat cryptic or its subject arbitrarily defined, but it is in fact quite appropriate once one understands the author's basic assumptions and concerns as outlined in his introduction and first three chapters. The geographical focus of the book is Iran-shahr, the term which Christensen uses to refer to the area from the Euphrates to the Amu Darya. This region, which he considers a more valid unit of historical inquiry than one such as the "Middle East," gains its coherence primarily from the environmental factors of aridity and the need for extensive irrigation in agriculture rather than political and cultural elements. The theme of the book is indeed the question of the widely perceived "decline" of this region from its classical glories to the sad shadow of itself in post-Mongol times - but in a much more disciplined and precise way than one usually finds in the historical literature. Christensen does not link the concept of "decline" to the fortunes of specific states or empires in Iranshahr but to the basic and fundamental index of agricultural production, the most important economic activity in all pre-industrial societies. This relegation of political history to a subsidiary, indeed almost negligible, role explains what might otherwise seem the peculiar methodological, thematic, geographic, and chronological boundaries of Christensen's study.

Although Christensen scrutinizes a rich selection of classical and Muslim textual sources, he makes it clear that he is not interested in "philological arguments." He relies most heavily on medieval records of tax assessments, but recognizes the limited availability and questionable...