After the tablets.

For the tablets, a long quiet begins. Alexander the Great enters Babylon in 331 BCE and intends to make it his eastern capital; he dies there two years later. His generals divide the empire. Seleucus founds a new Greek city across the Tigris from Babylon and calls it Seleucia. The administration moves there. Greek replaces Akkadian as the language of the court.

But cuneiform does not die immediately. In the temples of Babylon, Borsippa, and Uruk, the priesthood continues to write — for itself. Astronomical diaries, recorded nightly, accumulate uninterrupted into the first century BCE. Ritual instructions are recopied. The old lexical lists are still studied. Greek philosophers travel to Babylon to learn the planetary calculations of the Chaldeans — the late astronomy of the cuneiform tradition, which the West will absorb through Hipparchus and Ptolemy without always remembering its source.

The last datable cuneiform tablet is an astronomical text from 75 CE. After it, somewhere, some scribe almost certainly went on writing for years more. But the tradition fades. Aramaic, written in alphabetic letters on parchment, has become the everyday script of the region. The Parthians rule, then the Sassanians; in 637 CE the Arab conquest brings Islam, and Babylon, already abandoned for centuries, sinks under its mounds. The temples fall silent. The names of the gods are forgotten.

For nearly two thousand years, the wedges mean nothing. Travellers passing through Iraq see strange figures on broken stones — winged bulls with human faces, kings with curled beards in horned crowns — and ask the locals what they are. The locals do not know. Greek and Latin authors preserve fragments: Herodotus tells stories about Babylonian customs he half-understands; Berossus, a Babylonian priest in the third century BCE, writes a Greek history of his people that survives only in scattered quotations. The Hebrew Bible remembers Babylon as a place of exile and a tower that reached too high. The memory exists, but it is the memory of a closed door.

The door begins to open in the seventeenth century. European travellers — Pietro della Valle, Carsten Niebuhr — copy cuneiform inscriptions from Persepolis without understanding them. In the 1830s, a young British officer named Henry Rawlinson clambers up the cliff at Behistun in western Iran to copy the trilingual inscription Darius I had carved there in Old Persian, Elamite, and Babylonian. He and a small international community of scholars — Edward Hincks in Ireland, Jules Oppert in France, Fox Talbot in England — work out the system between them. By 1857, cuneiform can be read again.

The great recovery is in the 1850s, when Austen Henry Layard and Hormuzd Rassam excavate the mound of Kuyunjik at the abandoned site of Nineveh, and dig out the buried libraries of Ashurbanipal. Tens of thousands of tablets are shipped in crates to the British Museum and slowly catalogued. In 1872, a self-taught engraver named George Smith — by then an assistant at the Museum — reads a fragment and recognises in it a Babylonian story of a great flood: a man named Utnapishtim, a boat, a dove, a raven. He realises, sitting in the basement, that the Hebrew Bible is not the original. He runs around the room in his excitement. The Daily Telegraph sponsors his return to Nineveh to find the missing tablet, and he does.

The Mesopotamian past, sealed for two millennia, has been opened. In the century and a half since, French and German and American and Iraqi excavators have recovered hundreds of thousands of tablets from Nineveh, Nimrud, Babylon, Lagash, Ur, Eridu, Uruk, Nippur, Mari, and a hundred other sites. The Sumerian language, lost since 1700 BCE, has been reconstructed from scratch — guessed at, then refined through the long labour of bilingual texts and comparative grammar. Cuneiform, the oldest writing system in the world, can now be read better than it could be at almost any time in the last two thousand years.

But the work is far from finished. Of the half-million or so tablets in museum collections worldwide, only a small fraction have been translated into any modern language. Many of the most interesting — astronomical diaries running for centuries, legal records of forgotten kings, letters from court officials — have never been published at all. Mesopotamian studies remains a small field, and the tablets outnumber the scholars by a factor of a thousand.

This is where, perhaps, you come in. The point of this book is not to be the final word. It is to be a door, like the one George Smith opened in 1872. The tablets are still in the silt. The Sumerians and the Babylonians wrote them so they could be read. Two thousand years after the last tablet was buried, we are finally reading them. The story has a beginning. It does not yet have an end.