The textbook story of early cities runs in one direction: as settlements grow, wealth pools at the top. Kings, priests and elite families take control of land and trade, and the distance between the biggest houses and the smallest keeps widening. A new analysis of Mohenjo-daro, the largest city of the Indus civilisation, describes the opposite trajectory — a city that grew bigger, busier and more productive while its households grew more alike.
Adam Green, Iqtedar Alam and Cameron Petrie of the University of York reached that conclusion by measuring floor plans. Working from excavation records made at the site in the early twentieth century, they mapped house footprints and converted them into Gini coefficients, the same yardstick economists use to compare income and wealth today, where zero means perfect equality and one means everything held by one household.
Mohenjo-daro, which flourished between roughly 2600 and 1900 BCE in what is now Pakistan, scores 0.44 across its residential areas. Contemporary Mesopotamian cities such as Ur and Ugarit both exceed 0.6; Knossos in Bronze Age Greece reaches 0.86, and the Classic Maya city of Palenque 0.75. More striking than the comparison is the trend inside a single neighbourhood. In the district known as DK-G South, the largest houses of around 2500 BCE covered more than 160 square metres. Over the following four centuries, as the city filled in, the local Gini coefficient fell to 0.23 — a spread more typical of Neolithic farming villages than of a metropolis of tens of thousands.
What the city built instead
The physical record fits the numbers. Archaeologists have never found a palace at Mohenjo-daro, nor royal tombs stocked with gold, nor statues of rulers. What they have found is infrastructure: a grid of planned streets, standardised brick construction and a network of brick-lined drains running through ordinary neighbourhoods. Indus seals, the tools of trade and administration, turn up inside ordinary homes rather than locked away in public buildings, and a standardised system of weights and measures spread across the region, giving merchants and households a common basis for exchange.
The authors read this as evidence of collective investment rather than elite capture — resources directed at the services everyone used. Notably, the period when inequality appears lowest is also when productivity appears to rise.
"It challenges the idea that prosperity requires us to concentrate decision-making powers in the hands of the few," Green said, adding that the Indus case shows an urban society can be inventive and productive at scale while sharing resources broadly — and that doing so may have been part of what sustained it for centuries. The study appears in the journal Antiquity.