We inquire how a commodity cartel is created by studying the negotiations between Colombia and Brazil to stabilize the international coffee market in the 1930s. We show how differences among actors involved in the industry within the negotiating countries in terms of land ownership and type of coffee produced, prevented early cartelization agreements. Cartelization was only achieved when four factors converged: financial and infrastructural capability to store excess production, in-depth knowledge of the industry by the negotiating parties, full government support, and presence of a third-party enforcer. We combine an innovative game-theoretic approach with previously unexplored archival sources.