Between c. 300 BC and AD 350, the Meroitic kingdom dominated the Middle Nile Valley; following its breakdown, it was replaced by a series of smaller successor polities. Explanation for this change centres on socio-political and economic instability. Here, the authors investigate the role of climate and environment using stable carbon and oxygen isotope analyses of human and faunal dental enamel from 13 cemeteries. The results show increasing δ18O values towards the end of the Meroitic kingdom and in the post-Meroitic period, combined with less negative δ13C values. These trends suggest a shift towards more arid conditions associated with changes in agricultural practices and land use that may have contributed to the kingdom's dissolution.