This article traces the coming of a genetically modified (GM) cotton-agrochemical complex to highland eastern India. In this region of rich biodiversity and Indigenous systems of food and agroecology, GM cotton cultivation has seen a meteoric rise over the past decade. I explore how this shift from a no-input polyculture cultivation of community-held heirloom varieties to market-provisioned cotton seeds and agrochemicals marks a rupture that is fundamentally transforming the relationship of cultivators to land, seeds, and knowledge systems around agroecological practices. I contextualize this ongoing material and knowledge rupture in the specificities of location—both in an agroecological space and in a sociohistorical matrix of caste and region. Thus, what enables or erodes agroecological practices and ways of knowing is not simply the socioeconomic marginalization of smallholder cultivation, but more fundamentally a caste-prejudiced logic in India that, on the one hand, disrupts ecological ties of Indigenous communities to seeds, biodiversity, and land, and on the other denies the contributions of Indigenous knowledge, agriculture, and food cultures toward sustainability and biodiversity. This coming together of an industrial productivist logic with casteist prejudice is what I call casteist capitalism. Casteist capitalism structures both state programs of “tribal development” and agribusiness strategies in the region. Together they work to deride long-standing agroecological practices, and the Indigenous communities which practice them as “backward” and in need of reform toward a modern, commercial agriculture, as represented by chemical-intensive cotton monocropping.