In recent years, both International Relations and the subfield of critical border studies have shown that rigid borders and overpowering intentionality of states are a fiction. My paper contributes to these by making a new argument – it is the international borders, as anthropocentric assemblages, that inadvertently produce novel and unique agentic qualities among nonhumans who can then both stabilise and disrupt the borders. I theorise this nonhuman agency within anthropocentric borders by using Deleuze and Guattari's assemblage theory through the case study of rivers on the India-East Pakistan boundary at the time of Partition and the years after that. Through a relational development of the theory and an environmental history of the case, I demonstrate that India – East Pakistan boundary is not just a production of state elites, be it in 1947 or the years after that. Instead, it has been produced and modified – deterritorialized and reterritorialized – through the agency of the meandering Bengal rivers as well, particularly the Ganges.
