Egypt was unified around 3100 BCE, and the Old Kingdom raised the pyramids of Giza as resurrection machines for its kings, the largest buildings on earth for nearly four thousand years. After a first age of breakdown, the Middle Kingdom classicized the language and literature, and the New Kingdom built an empire from Nubia to Syria, pouring its wealth into Karnak, the greatest temple complex ever constructed, and into the royal tombs of the Valley of the Kings. Akhenaten's attempt to replace the gods with the single solar disk Aten lasted one reign before Tutankhamun's court restored the old cults, an episode preserved in the record precisely because it failed.
Abydos, burial place of the first kings and cult home of Osiris, drew pilgrims for the whole of Egyptian history, and the Oxford History edited by Ian Shaw traces that history through Libyan, Nubian, Persian, Greek and Roman rulers, each of whom found it easier to become pharaoh than to replace what pharaoh meant. Under the Ptolemies the cult of Isis spread across the Mediterranean world, and her temple at Philae remained active into the sixth century CE.
Christianity ended the temples but not the language: Coptic, the last stage of Egyptian written in Greek letters, remains the liturgical tongue of Egypt's church. The script itself slept from the last hieroglyphic inscription of 394 CE until Champollion's decipherment in 1822 opened three thousand years of texts, from Miriam Lichtheim's translated literature to the spells of the Book of the Dead, to modern readers.