Abstract: Indigenous peoples worldwide face significant health disparities rooted in colonial legacies, including displacement, socioeconomic marginalization, and discrimination. The focus of this chapter is colonialism as a determinant of Indigenous health, emphasizing its structural impact on social, cultural, and economic well-being. It compares global case studies to demonstrate how colonialism continues to impact Indigenous health outcomes, including high rates of chronic diseases, mental health issues, infant mortality, and overall lower life expectancy. There is attention to the importance of understanding Indigenous conceptions of health and strengths-based analyses that emphasize holistic well-being and community harmony. While recent studies emphasize decolonization and reconciliation as pathways to address Indigenous health disparities, it is critical to recognize that a failure to address structural injustices is ultimately colonialism in disguise. This chapter highlights a requirement to recognize rights to land, culture, and sovereignty to address colonialism as a determinant of Indigenous peoples’ health.