Archaeological and environmental research by an international and interdisciplinary team opens new perspectives into the settlement histories of Kansyore, Early Iron Age, and Bigo period peoples in the once forested regions of the Ndali Crater Lakes Region (NCLR) of western Uganda. The research examines the role of Kansyore agropastoralists and their Early Iron Age and Bantu-speaking contemporaries in remaking a once forested environment into a forest-savannah mosaic from circa 500 BC to the end of the first millennium AD. Archaeological settlement and subsistence evidence is examined within a framework of social interaction of Sudanic speakers with Bantu speakers, drawing on historical linguistics and environmental studies to arrive at a new synthesis of late Holocene history in western Uganda. This perspective also unveils the significance and chronology of Boudiné ware, a long enigmatic ceramic tradition that we identify as contemporary to Transitional Urewe and deeply influenced through social interactions with those making Kansyore ceramics and inhabiting the same landscape. Using archaeological evidence from fifteen sites and multiple burials spanning from 400 to 1650 calAD, new views of ceramic histories, lifeways, and symbolic values are revealed, including Bigo period settlements that arose in what was an environmental refugium beginning in the early fourteenth century AD. This research also shows that the Kansyore of the forested region east of the Rwenzori Mountains had greater affinities to late Holocene archaeological evidence from western Equatoria, in the southern South Sudan, and Kansyore Island, Uganda, than it does to the Kansyore in eastern Kenya.