In Empires in Collision in Late Antiquity (Brandeis University Press, 2012), Glen W. Bowersock, Professor Emeritus in the School of Historical Studies, examines political developments in the Arabian Peninsula on the eve of the rise of Islam. Recounting the growth of Christian Ethiopia and the conflict with Jewish Arabia, he describes the fall of Jerusalem at the hands of a late resurgent Sassanian (Persian) Empire and concludes by underscoring the importance of the Byzantine Empire’s defeat of the Sassanian forces. Using close readings of surviving texts, Bowersock sheds new light on the complex causal relationships among the Byzantine, Ethiopian, Persian, and emerging Islamic forces.