Mediterranean Anarchy, Interstate War, and the Rise of Rome (review)

The study of war and state formation has traditionally occupied a prominent position in the academic field of ancient history but is generally conducted without the benefit of formal theorizing. In a welcome and long overdue attempt to address this deficit, Eckstein provides a pioneering analysis of the causes of interstate conflict in the Greco-Roman world, and, more specifically, of the motivations behind Roman expansion and the reasons for its success, from the perspective of realist theory. An up-to-date survey of contemporary realist theory introduces historians to the key premises of this study (12–36): that in a system of militarized anarchy, states are driven to increase their power; that they are highly sensitized to potential threats; that they aim, whenever possible, for preclusive expansion to construct outward-facing systems of security, and in all of these respects trend toward functional similarity; that the prevalence of war is determined by balances of power, and the multipolar state-systems of the ancient Mediterranean increased the likelihood of conflict; and that power-transition crises (caused by sudden shifts in power relations) may trigger system-wide or "hegemonic" warfare.

Eckstein's principal objective is to stress "the previously unacknowledged role of system-level factors, both in the causation of warfare in the ancient Mediterranean and in the rise of Rome to world power" (35). Realist readings of interstate relations in classical Greece (highlighting the Thucydidean roots of this school of thought) and among the major Hellenistic powers set the scene for his revisionist interpretation of Roman expansion (37–117). Eckstein devotes two core chapters to a comprehensive and ultimately devastating attack on traditionally dominant "unit-attribute explanations" of Roman militarism and empire-building that privilege domestic properties of Roman society in accounting for ultimate outcomes in state formation (118–243).

After demonstrating that the anarchic environment of the ancient Mediterranean molded Rome's main rivals for power (Etruscans, Gauls, Samnites, Tarentum, and Carthage) into comparably warlike and expansionist polities, Eckstein critiques the popular thesis of "exceptional" Roman bellicosity (as a putative cause of Rome's successful expansion) by surveying foreign parallels to a number of Roman institutional features that are customarily invoked to support that notion. He maintains that from a Realist perspective, such traits are best understood as the almost inevitable products of the profoundly anarchic and intensely competitive environment of the ancient Mediterranean: If the Roman state was indeed a "war machine," so were its neighbors.¹ Eckstein's argument underscores the crucial importance of explicit cross-cultural comparison, which to this day remains exceedingly rare among ancient historians. It deals a heavy blow to the blinkered ad hoc reasoning (in itself a by-product of the disciplinary cult of the so-called "Classics") that has long constricted and intellectually isolated the academic training and research projects of ancient historians.

Eckstein advocates a realist "pull"model according to which Rome's expansion drew it into ever-larger and previously separate zones of interstate conflict (what world-systems theorists would call "political-military systems"), thereby causing them to merge for the first time in history and creating a pan-Mediterranean unipolar hegemony that eventually developed into a "core-wide" empire (257–316). This convincing demonstration of the underlying causes of war and conflict allows us to focus on the problem of unequal outcomes: Why did Rome succeed on the scale that it did?

In some respects, Rome was truly unique, the only power ever to unite the entire Mediterranean region and the only European empire west of Russia that rivaled the great empires of the Middle East, India, and China in scale and longevity. Eckstein devotes only a small portion of his work to this vital question, emphasizing the superior military mobilization potential of the Roman state (245–257). However, his allusion to an emergent Roman "nation-state" is misleading.² What matters here and remains to be explained is the striking capacity of the Roman state...