The volume examines the late Byzantine world, describing a religious schism between Greek and Latin churches and the political fallout from a failed ecclesiastical union. It juxtaposes a vivid picture of Constantinople's former magnificence with its physical decay and civic disorder, traces military and diplomatic maneuvers involving Amurat, Ladislaus, Giovanni Uniade, and Scanderbeg, and recounts the emperor's efforts to rally defense. The account culminates in the siege, the emperor's death, and the capture of the capital, showing how internal division and external pressure combined to end imperial rule.