Ethnographic and archaeological data from the Mapungubwe landscape show that rainmaking deposits on hilltops, along with burnt grain bins in ordinary villages, represent cultural responses to severe drought by Iron Age agricultural communities. In ordinary villages, burnt granaries were the result of cleansing rituals, rather than violence or natural causes. A total of 13 episodes of severe droughts were previously documented in hilltop and village deposits. New climate proxy data from baobab trees provide a 1000-year-long regional record that helps to refine this drought sequence. Based on carbon isotope values, the baobab record documents additional episodes and confirms an early 14th-century drought associated with the abandonment of Mapungubwe. This abandonment, however, owed as much to cultural factors as to environmental pressures.