In this article, I trace the credit and debt practices of a company incorporated in the UK to extract "wild rubber" in the Amazon. Based on reports by Sir Roger Casement, an officer of the British diplomatic service, I present a general description of the organization of the Peruvian Amazon Co., whose operation did not depend on investment in technology or infrastructure but, rather, on the flow of credit in the form of merchandise. I will discuss debt-peonage as the form of labor privileged by the wild rubber industry in the Amazon and show how it works when indigenous peoples and their territories are involved, as was the case in Putumayo. I argue that the concept of debt-peonage is misleading in this situation, as it obscures both the conditions and the relations into which the Indians, as a society, were forced. I will highlight the role of debt in this relation, commonly referred to as the "conquest" of the Indians, as constitutive of both physical and symbolic violence. I conclude showing how credit and debt, usually considered to be instrumental for the development of capitalism, are here at the core of a system that not only was opposed to the logic of the market, but also strangled local production and exchange networks. The "credit engine" became here an instrument of genocide.