This volume contains the proceedings of the twenty-first annual British Museum International Egyptology Colloquium, which was the first in the series dedicated to post-pharaonic Egypt. The volume investigates continuity and change in the archaeological record in the First Millennium AD, focusing on the transitions to and from Late Antiquity (AD 250-800), when Egypt's population became Christian and, later, Islam was introduced. The fourteen contributors, representing the overlapping disciplines of Egyptology, Archaeology and Art History with specialisations in the pharaonic, Roman and Late Antique periods, present the results of new archaeological research at a range of sites currently under investigation. Seeking to identify trends and compare results, the volume is organised according to four major themes: 1) settlements, 2) cemeteries, 3) settling rock-cut tombs and quarries and 4) temple-church-mosque. Many of the contributions address adaptive reuse of earlier architecture, the recycling of earlier monuments as building material (i.e., spolia), or both. Traditionally neglected by modern scholars in favour of other periods in Egypt's long history, the study of First Millennium AD archaeology offers increasingly better opportunities to evaluate both Egypt's distinctiveness and its role within the wider Mediterranean region.