The Palagua swamp in the Middle Magdalena region of Colombia is a territory governed by nearly a century of petro-development and armed conflict. This toxic reality, along with the disappointment of temporary legal victories and demands for environmental compensation, have left deep marks on individuals’ psyche, eroding the self-confidence and spirit of communities. Drawing on archival research, secondary regional sources, and 13 semi-structured interviews with former oil workers, fishers, farmers, and women activists, we delve into the meaning, implications, and transformation of petro-development and internal colonialism. We suggest that the decolonization of being in a petrolized environment implies challenging imposed imaginaries of development and perceiving forces of internal colonialism. This should be recognized as a long-term process, a painful incubation of possibilities, marked by persistent and transformative day-to-day actions.