The dates and circumstances of early references to Jenne have led historians to conclude that the city originated relatively late in time. It is widely believed that the city developed simultaneously with Timbuktu in the mid-thirteenth century as an artifact of trans-Saharan trade. Persistent oral traditions of the foundation of Jenne in the eighth century are generally discounted.
Recent archaeological excavations at the ancestral site of Jenne-jeno have established that iron-using and manufacturing peoples were occupying the site in the third century B.C. The settlement proceeded to grow rapidly during the first millennium a.d., reaching its apogee between a.d. 750 and 1100, at which time the settlement exceeded 33 hectares (82 acres) in size. The archaeological data are supported by the results of site survey within a 1,100-square-kilometre region of Jenne's traditional hinterland. During the late first millennium a.d., several nearby settlements comparable in size to Jenne-jeno existed, and the density of rural settlements may have been as great as ten times the density of villages in the hinterland today.
Evidence from excavation and survey indicates that Jenne participated in inter-regional exchange relations far earlier than previously admitted. The stone and iron in the initial levels at Jenne-jeno were imported from outside the Inland Delta; levels dated to c.a.d. 400 yield copper, presumably from distant Saharan sources. The importance of the abundant staple products of Jenne's rural hinterland, including rice, fish and fish oil, is examined in a reassessment of the extent of inter-regional commerce and the emergence of urbanism during the first millennium a.d. Jenne-jeno may have been a principal participant in the founding of commercial centres on the Saharan contact zone of the Bend of the Niger, rather than a product of the luxury trade serviced by those centres.