Why did the Bronze Age collapse?

Major centres were destroyed or abandoned across Greece, Anatolia, Cyprus and the Levant, at different places at different times across about two centuries, with the heaviest destructions around 1200 BC. How many of those destructions happened is itself argued: a 2023 reassessment by Jesse Millek rejects 94 of 153 destructions proposed for about 1200 BC as misdated, assumed or miscited, though the end of the palace states of Greece is not in doubt. It was not uniform: many Levantine towns were reoccupied after short abandonments. The Hittite empire ends and its capital, Hattusa, is emptied and abandoned; the written record it kept stops, though smaller successor states carry on in the south-east. Ugarit, a wealthy port whose tablets preserve its kings’ letters to the end, is destroyed around 1190 BC.

The Linear B script disappears with the palaces, and writing does not return to the Aegean until the alphabet spreads in the eighth century BC. Long-distance trade, which is what supplied the tin that bronze requires, stays limited for four centuries.

Pollen records from coastal Syria and Cyprus show a shift to markedly drier conditions from about 1200 BC, lasting some three hundred years. Oxygen isotopes from a cave in Israel and from cores off the Israeli coast carry the same dry interval.

At Gibala-Tell Tweini, on the Syrian coast, the radiocarbon dates for the start of the drought and for the town’s destruction are statistically indistinguishable, around 1200 BC. The Cyprus core shows agriculture returning as the drought ends, in the ninth and eighth centuries BC. Cuneiform correspondence from the same decades records food shortage, a case where a written record and a sediment core can be set side by side.

Tree rings from Gordion in central Anatolia add a sharper event inside the long one: three consecutive years of severe drought around 1198 to 1196 BC, give or take three years, as the Hittite empire fell. Most other records are too coarse for that. Drake notes that every proxy he assembled is low-resolution, and the Gordion team writes that in several such comparisons the dates are too loose to test a correlation, let alone a cause.

A 2012 review set the archaeology of Greece against the climate proxies available for the same centuries, among them a cave speleothem in Israel, carbon isotopes from a pollen core at Lake Voulkaria in western Greece, and alkenone sea surface temperatures, dinocysts and foraminifera from Mediterranean sediment cores. Most of them make the Early Iron Age drier than the Bronze Age before it, though not every record lines up and one core, from the Levantine Basin, shows no change. A 2026 climate simulation qualifies the picture: it reproduces the drying in the Levant but gives parts of the Balkans and Anatolia more effective moisture, because cooling reduced evaporation and transpiration.

Records of different kinds, at opposite ends of the collapsed world, pointing the same way, are a stronger argument than any one core. The proposed mechanism is a cooling Mediterranean: colder sea surface means less evaporation, and less rain over the land.

It also lines up with the interval conventionally called the Greek Dark Ages, which follows the palaces and stays arid until the Roman Warm Period.

Egyptian inscriptions record wars with Sea Peoples from the Nile Delta to the Levant, from the reign of Ramses II to the reliefs of Ramses III at Medinet Habu. The label is broad and probably covered many groups.

One reading makes them invaders who caused the collapse. Another makes them displaced populations, moving because their own homes had already failed, which would make them a symptom.

The climate papers cited here favour the second: not pirates in pursuit of Near Eastern wealth, but groups leaving regions that had stopped supporting them. They do not settle who the Sea Peoples were or where they came from, and Kaniewski’s team says so.

The account Drake calls dominant is economic systems collapse: once trade relationships broke down, rulers could not keep control of their districts, polities dissolved, and no central authority could be rebuilt.

Bronze requires tin, and tin was scarce. Copper lay within reach of every major state, but most tin deposits lay far from the cities, and a cargo wrecked off the Turkish coast around 1320 BC carried tin from the Taurus Mountains and from Central Asia. A kingdom that loses its trade routes loses its bronze. That is a specific mechanism for how a local failure becomes a regional one, and it is a model rather than a demonstration.

Populations fell sharply at the destroyed centres. Whether people died, dispersed into smaller settlements, or moved long distances is known in detail almost nowhere, because small, scattered and mobile populations leave little for archaeology to find.

The collapse is documented mainly through the buildings and archives of elites, which is a systematic bias in what can be said about it.