Environmental history, as a field of analysis and transdisciplinary study, aims to explore the interactions between society and ecosystems from a deep understanding of how relationships between human groups and natural systems change over defined periods of time. This article seeks to delve into the environmental history of the savannahs of the Cesar department in Colombia, documenting the milestones in the privatization of the commons and the degradation of social–ecological systems. Methodologically, satellite images and aerial photographs are analyzed to determine the changes in land cover that reveal the state of the ecosystems, and an ethnographic approach is used to document the perception and valuation of local Afro-descendant communities in the region. The article shows how, over the last 60 years, land-use planning models have favored individual appropriation practices and agroindustrial models over collective forms of pastoralism and small-scale agrifood systems. It also documents the main socio-ecological impacts and the conflicts implicit in different tenure models that should be taken into account in the various public policies related to sustainability, peace building, and the recognition of territorial rights in the Colombian Caribbean.