Indigenous stewardship and conservation initiatives within the Hudson – James Bay Lowlands and adjacent marine areas have stimulated research about carbon, biodiversity, and causes and consequences of environmental change. Across this region, unique terrestrial, wetland, and marine ecosystems support critical habitat and provide globally significant carbon stocks and sinks. However, this region is undergoing climate-driven changes to sea ice, ecohydrology, and permafrost, together with economic development, which may bring new challenges to First Nations communities and drive feedbacks to the global carbon budget. Understanding the impacts and planning for a sustainable future require bridging Indigenous and scientific knowledge systems and extending analyses across boreal - peatland - coastal zone transitions.