The period between 150 and 750 AD. e. - an era in which seemingly the most immutable ancient institutions disappear forever. By 476, the Roman Empire had ceased to exist in Western Europe, and by 655, the Persian Empire had ceased to exist in the Middle East. Peter Brown's now classic study is an attempt to understand what distinguished the late ancient world from classical ancient civilization and how these changes predetermined the different development paths of Europe and the Middle East. The author explores social transformations and contemporary reactions to them in order to answer one of the key questions of world history: how and why the Mediterranean world around 200 AD. e. broke up into three different societies of the Middle Ages - Catholic Western Europe, Orthodox Byzantium and the Islamic Middle East? Peter Brown (b. 1935) - one of the founders of late antique studies, professor of history at Princeton University.