Mesopotamian civilization — Sumer, Akkad, Babylon, Assyria — gave the world its earliest written literature, including its earliest written eschatology. The afterlife these texts describe is grim. The House of Dust, Kur or Irkalla or Arallu depending on the period and dialect, is beneath the earth, ruled by Ereshkigal, the queen of the great below. The dead descend through seven gates, each of which strips them of some further article of clothing or ornament, until they arrive naked and powerless before Ereshkigal's throne. They eat clay. They drink muddy water. They flap like birds. They are clothed in feathers. There is no reward and no punishment, only diminishment and dust.
This is the afterlife that shaped everything Mesopotamian. Gilgamesh, the greatest of heroes, confronts it when his friend Enkidu dies, and the second half of the Gilgamesh Epic — one of the oldest sustained literary works known — is his desperate, doomed attempt to escape it. He travels to the edge of the world, to the garden of jewels, to the ferryman Urshanabi, across the Waters of Death, to the flood hero Utnapishtim who alone has been granted immortality. Gilgamesh fails. He is told: when the gods made humanity, they allotted death to humanity and kept life for themselves. He returns to Uruk with no prize except the wisdom of his own wall, which will outlast him, and a sober acceptance of the limits of his life.
The Descent of Inanna (in Sumerian) and its later Akkadian version, the Descent of Ishtar, narrate another encounter with Irkalla. Inanna, queen of heaven, goes down to her sister Ereshkigal, ostensibly for the funeral of Ereshkigal's husband, actually to seize the underworld itself. At each of the seven gates she is forced to remove a garment or jewel — her crown, her earrings, her necklace, her breastplate, her belt, her bracelets, her last garment — until she stands naked before Ereshkigal. Her sister hangs her corpse on a hook for three days. Only through a ruse by Enki, the god of wisdom, who fashions two sexless beings to sneak into the underworld and mourn Ereshkigal's own suffering, is Inanna rescued; but the underworld demands a substitute, and Inanna's unfaithful husband Dumuzi is taken in her place. Dumuzi's annual descent and return is the seasonal myth that underlies the vegetation cycle across the ancient Near East.
What makes Mesopotamian eschatology distinctive is its bleak honesty. The tradition does not soften death. There are no gardens. There are no rewards for the virtuous, except insofar as a well-tended tomb and descendants offering regular libations could keep the shade of the deceased from becoming especially hungry and troublesome to the living. The ancestor cult was not about piety; it was about maintenance. Neglect the dead and they would return as gidim — restless, malevolent ghosts — and bring illness, nightmares, misfortune.
The answer Mesopotamia gave to mortality was not in the afterlife. It was in this life. Gilgamesh's last words to his ferryman, showing him the walls of Uruk, are a summary of the whole tradition: look at these walls. Look at this city. This is what remains. Live well, eat well, lie with the wife you love, love your children, build what you can. The dead go to the dust, and what is remembered of them is what they built while they were here.