Qustul dries out while Upper Egypt fills up

Between 3300 and 3100 BCE the Qustul kingdom lost wealth and power as desiccation thinned out the populations of the country around it. Lower Nubia has little arable land beside the river. Upper Egypt has a great deal more, so as people left the drying hinterland the polities there could support far larger populations and raise far larger armies. Three things followed in the last three centuries of the fourth millennium BCE. One or more large polities took shape in the Naqada regions of Upper and Middle Egypt. Writing was invented. Then, in the thirty-first century, rulers of the First Dynasty unified the Nile from Aswan to the delta. The centre of gravity moved north while the cultural material stayed where it was. People arriving from the dying desert carried with them the ritual practice, the royal imagery and the idea of sacral kingship that this region had been developing for three thousand years.

The First Dynasty royal tombs at Abydos hold more than kings. Around them lie the graves of retainers and high-status people put there to accompany the ruler and look after him afterwards. Hor-Aha has thirty-six such burials. His successor Djer has as many as three hundred and eighteen. Djet has one hundred and fifty-four, and Den, the fifth ruler, has one hundred and thirty-five. The practice was neither confined to Egypt nor started there. It appears equally early further south, it was still going in the second millennium BCE at the height of the Kerma kingdom on the Upper Nubian Nile, and it recurs across a long line of Nilo-Saharan-speaking or Nilo-Saharan-influenced states in the Sudan belt, from pre-Christian Nubia to the Wagadu empire of the Ghana in the ninth century CE. Egypt is one branch of that tradition. It kept retainer burial for a few generations and then let it go.

Egypt was divided into districts, the nomes, and each nome had its own god. That arrangement is a leftover. Before the Old Kingdom, the people of the Nile valley held the henotheistic belief system common among early Afrasian speakers, in which a community gives its primary allegiance to a local god while accepting that other communities have theirs. When the first kings unified the valley they recognised those local gods rather than suppressing them, which gave every district a stake in the new order and cost the crown nothing. A second tier appeared alongside them: national gods such as Osiris, Isis and Horus, tied to the kingship and acknowledged everywhere. The result is the polytheism the textbooks describe, and it is a composite. Local henotheism from the pre-state era sits underneath a national pantheon installed on top of it. The lower layer traces back through proto-Erythraic to the Horn of Africa.

Hor-Aha, first or second king of the First Dynasty, sent his forces south and destroyed what remained of the Qustul state. The southern frontier of the Old Kingdom was fixed by that campaign and held for centuries afterwards. He did it wearing the White Crown that a Qustul ruler had worn before him, attended by the Horus falcon that had attended a Nubian king, carrying an idea of sacred kingship developed upriver in the country he was burning. The Old Kingdom that followed went on displaying its inheritance in plain sight. Its political institutions and its ritual observances kept the marks of the wider Middle Nile world they came out of, in the ceremonies around the king, in the handling of royal death, and in the claim that a ruler holds divine authority. Conquest ended the kingdom. It left the kingdom intact inside the conqueror's own practice, where it is still legible.