Between AD 285 when Byzantium first separated from the Western Roman Empire and 1461 when the last Byzantine splinter state disappeared the Byzantine state and society underwent many crises triumphs declines and recoveries. Spanning 12 centuries and three continents the Byzantine Empire linked the ancient and modern worlds shaping and transmitting Greek Roman and Christian traditions including the Greek classics Roman law and Christian theology that remain vigorous today not only in Eastern Europe and the Middle East but through western civilization. This book examines the causes behind Byzantium's political leadership military strategy cultural attitudes and social institutional and demographic changes combined with the strengths and weaknesses of the empire's enemies to explain the paradoxes of Byzantium's long history.