The pyramid age began after a centralised polity formed along the Lower Nile in the late fourth and early third millennia bc and ended before Egypt rose to empire in the second half of the second millennium. It saw the unfolding of the Egyptian state, which affected the lives of people across north-east Africa. Archaeologists equate the pyramid age with the Early and Middle Bronze Ages, so these terms are frequently found in discussions of synchronisms across the Mediterranean and the Near East, but they are uncommon in Egyptology when describing internal developments in Egypt and interactions with societies in north-east Africa. From the later nineteenth century ad, the pyramid age was subdivided into the Old and Middle Kingdoms. The term First Intermediate Period, a period portrayed retrospectively in ancient Egyptian texts as a time of chaos, only became widely used after the First World War, possibly in response to contemporary experiences following the breakdown of the European concert of powers.1