The Rain Forest Savanna Contact (‘ReSaKo’) project focused on providing geoscientific evidence for past environmental change. The research groups’ activities focused on examining the temporal and spatial coherence of altering land-use strategies, cultural innovations and climate change during the so-called ‘First Millennium BC Crisis’. For this approach the ecologically sensitive ecosystem of the tropical southern Cameroonian evergreen to semi-deciduous rain forest and its adjacent savanna margin had been selected.