Walter E. Kaegi, Muslim Expansion and Byzantine Collapse in North Africa, Cambridge 2010

Walter E. Kaegi is professor emeritus for byzantine history at the University of Chicago. His period of study ranges from the fourth to the eleventh centuries, with the conflict between Islam and the Eastern Roman Empire in the Middle East, Anatolia, and North Africa as the focus of his research.

Walter Kaegi addressed this gap in his study „Muslim Expansion and Byzantine Collapse in North Africa“. The transition between Byzantine rule in North Africa and the Arab conquest is one of the huge desiderata of research on North Africa. Kaegis attempt is „to reexamine materials in the light of new discoveries about seventh-century Byzantium and about Byzantine relations with Arabs and Muslims in the seventh century, and with respect to changing interpretations of broader conditions in the Late Antique world of the seventh century” (10). The book is divided into twelve chapters, which, in addition to political and military history, also highlights geographical, cultural-historical, social and religious topics.

The first Chapter provides a helpful chronological table for the events in North Africa between 535 and 711 AD. This is followed by an analysis and presentation of the existing Roman and Arabic sources in Chapter 2, and the challenge and problems they offer.In the third chapter, Kaegi describes the microregions and natural structures of North Africa, which, according to the author, were largely too unfamiliar to the Byzantines to develop effective defense concepts. However, the real political fragmentation of the ruling areas probably played a role as well.

The fourth chapter is devoted to the confessional disputes within the Christian communities of North Africa under the emperors Heraclius and Constans II. According to Kaegi the disputes among the North African Christians would have prevent an effectibe defense of the provinces against the Arabs. In the fifth chapter Kaegi deals in detail with the military Byzantine administration. According to his thesis, the defense of the provinces focused only on defending key cities and smaller regions, instead of considering a linear and effective land defense strategy.

The shock of Sbeitla is dealt within the sixth chapter of the book. It examines the great defeat of the exarch Gregorios in 647 at Sufetula against an Arab army advancing from Tripolitania. Since the source situation for this central event is conceivably poor, Kaegi’s reflections on the course of the battle remain hypothetical. The battle marked a turning point in the course of the Byzantine defense. After the battle, the Byzantine administration temporarily collapsed. According to the Byzantine sources, Gregorios fled to Carthage, while the Arab sources unanimously report the death of the exarch. Continuing Arabian raids in the aftermath led local provincial elites to pay tribute on their own. After that the imperial administration succeeded in stabilizing and consolidating temporarily, but in the long term this failed due to technical, financial and personnel problems in the region (chapter 8).

The reign of Constans II occupies a central role in chapter 8, which Kaegi regards as a decisive turning point in the collapse of Byzantine North Africa. After a renewed period of raids and looting by the Arabs in the 660s, there was a growing tendency among provincial elites to pursue increasingly independent local policies from Constantinople. With reference to Arab sources, Kaegi sees here the increasing will of local populations to accept Arab rule. Kaegi places the increasing conquest of North Africa in the larger context of Arab expansion in the following chapter 9. In particular, the attacks on Asia Minor tied up Byzantium’s forces in the east of the empire and left the peripheral provinces in the west to fend for themselves.

The further collapse of the provincial administration is described in the following chapter. Independent Berber states(„autochthonous tribal groupings” (223)) that detached from Byzantium seem to have offered greater resistance to the Arabs in Numidia and the Aurés region than the Romans did. However, a detailed consideration of the nomadic and sedentary populations of this region is lacking. The conflicts with the Berbers continued even after the capture of Carthage in 695/696, which marked the end of Byzantine rule and resistance in North Africa (Chapter 11).

In the final chapter Kaegi discusses the reasons of the Byzantine collapse in North Africa. According to him the African provinces never developed an efective defense strategy and missed to poss the necessary resources for an effective defense. Moreover, the imperial government was never able to reach an agreement with the Berber units and integrate them specifically into the defense of the provinces. Moreover, Kaegi suspects that, in contrast to the ongoing confessional conflicts within the African Christians, Islam gave a “new cohesiveness” (270). Kaegi deliberately leaves aside the question of the continuation of Christianity in North Africa after the Arab conquest. Here, continuities were still apparent for a long time. The Arab conquest therefore doesnot necessarily represent a caesura for the time being.

In total, Kaegi addresses some central questions of continuity or discontinuity between Byzantine and Arab North Africa, which makes this book extremely valuable for the study of war and conquest in late antiquity. Despite the poor state of the sources, Kaegi skilfully describes the final phase of the Byzantine exarchate of Carthage. The book makes an important contribution to the rarely considered period of the 7th century, which has otherwise hardly been covered monographically. However, Kaegi only covers the Roman and sedentary part of late antique society. A consideration of the nomadic Berber groups would have enriched the study, since, as Kaegi himself mentions, they apparently resisted the Arabs much longer and more effectively and played a decisive role in the further course of the Arab conquest of the Maghreb and the Iberian Peninsula.