This essay focuses on the Senecas of western New York and their transformation, resilience, and resistance in the early nineteenth century. Rooted in a hybrid economy and environmental practice, among the postcolonial threats they faced in the context of white territorial expansion, republican and capitalist ideology, was an emerging new instrumental view of property, a radically changing economy, and embryonic ideas about “conservation.” Colonial expansion in the early American republic came at the expense of the Senecas and other Indians—or least that was the design. This expropriation has often been less visible because its story mostly is told from the perspective of (white) nationalism, democracy, and expanding opportunity embedded in the promise of “life, liberty, and the pursuit of happiness.” In addition, such colonialism in the nineteenth century and into the twentieth has often been masked by another emerging, “greenish” ideology, that of conservationism. Native (residual) rights, autonomy, and sovereignty could be ignored or overwhelmed by the supposedly objective, universal, scientific, and progressive demands that land and resources be conserved, not only from outsiders, but from Native people themselves. Thus, occurring at the expense of American Indians and environmental justice, conservation could be as exploitive and unjust as development.