Whether measured by the period during which it has been celebrated, the frequency with which it has been held, or the cumulatively vast numbers of people who have participated in it, the Eucharist has been central to Western life. The book explains how it developed during the first thousand years, from the time of its inauguration by Christ at the Last Supper to the beginning of the great schism between the Orthodox and Catholic Churches. The Eucharist was a central part of society in late antiquity and the Middle Ages, and it throws unexpected light on the lives and attitudes of the countless men and women who attended it and took communion. John Moorhead is Professor Emeritus at the University of Queensland. His books include Gregory the Great (2005) and The Popes and the Church of Rome in Late Antiquity (2015).