Book excerpt: The Byzantine Empire was the Islamic commonwealth’s first and most stubborn adversary. For many centuries it loomed large in Islamic diplomacy, military operations and commerce, as well as in Islamic representations of the world in general. Moreover, the ways in which early Muslims and Byzantines perceived one another ” both polemically and otherwise ” afterwards proved decisive for the mutual perceptions between the Islamic world and Christian Western Europe. For these and other reasons, Arab-Byzantine relations have been a major concern of modern scholarship on early Islam for well over a century. Arab-Byzantine Relations in Early Islamic Times presents some of the most important of these contributions, organized according to the following themes: war and diplomacy; frontiers and military organization; polemics and images of the 'other'; exchange, influence and convergence; and martyrdom, jihad and holy war. An introductory essay discusses these themes within the contexts of early Islamic society, politics and economy.