The second chapter traces the Brazilian reaction to the developments across the border in Argentina, which led federal politicians and local park boosters to establish a protected area of their own, the Iguaçu National Park in 1939. The Brazilian government created Iguaçu in the context of the “March to the West,” the 1940s federal campaign to occupy Brazil’s hinterland as a solution for an underdeveloped frontier. But the park’s creation also reveals the crucial role of local politicians and other intermediary agents in pushing for policies of territorial development. Park proponents, including state governors and local politicians, were aware of the national park being established in Argentina and used it as leverage for pushing for a national park on the Brazilian side of the Iguazu Falls. Their activism proved decisive in the establishment of the park in Brazil. The dialogue between local actors and the seat of power in Rio de Janeiro shows how territorial control is never exclusively a top-down process.