Focusing on Henry David Thoreau’s ‘Indian’ studies, in particular his widely popular The Maine Woods (1864), and writing from within the discipline of religious studies and specifically American religious history, I locate Thoreau squarely in nineteenth-century religious liberalism. This allows for a more historicized reading of his thinking on nature. Interplay between religion and natural history in Thoreau’s writing unfolded with respect to competing views of nature in nineteenth-century America. In his studies of Maine’s Penobscot Indians Thoreau attempted to wed the natural and supernatural realms. Many nineteenth-century religious liberals engaged in a similar project as they wrestled with their dilemma of whether to salvage or jettison religion as a whole. Instead of signaling a decline in creativity, imagination, or power, Thoreau’s substantial research and writing on Native Americans near the end of his life are an indication of important personal and cultural conflicts over the meaning of nature.