During the fourth millennium BC, public institutions developed at several large settlements across greater Mesopotamia. These are widely acknowledged as the first cities and states, yet surprisingly little is known about their emergence, functioning and demise. Here, the authors present new evidence of public institutions at the site of Shakhi Kora in the lower Sirwan/upper Diyala river valley of north-east Iraq. A sequence of four Late Chalcolithic institutional households precedes population dispersal and the apparent regional rejection of centralised social forms of organisation that were not then revisited for almost 1500 years.