Deforestation in Colombia, driven by armed conflict and illicit crops, triggered an environmental crisis, particularly in the Caribbean region, where forest loss in areas such as the Sierra Nevada de Santa Marta degraded ecosystems, reduced carbon sequestration, and increased soil erosion, threatening biodiversity and local food security. In response, the Arhuaco Indigenous community implemented an ethnic territorial management system to restore degraded lands and safeguard their ancestral territory. This study evaluates the effectiveness of their efforts, supporting their call for territorial expansion by analyzing forest cover changes (1973–2023) in the Tucurinca and Aracataca river basins. Using Landsat imagery, remote sensing, and a maximum likelihood algorithm, we generated thematic maps and statistical vegetation change data, validated by a 91.4% accuracy rate (kappa coefficient and confusion matrices). Results demonstrate significant forest recovery, highlighting collective reforestation and Indigenous sustainable management as pivotal strategies for reversing deforestation in post-conflict scenarios.