This book is located at the intersection of world-literary studies and the environmental humanities. Focusing on the period 1890-1950, it analyses how fiction and poetry respond to the ecological transformations entailed by commodity frontiers. Broadly speaking, commodity frontiers are zones of extraction or production that reorganize human and nonhuman natures in such a way as to send vast reservoirs of relatively cheap resources into the world-economy. Examining the sugar, cacao, coal, and oil frontiers in Trinidad, Brazil, and Britain, the book shows how literary texts have registered the relationship between the re-making of biophysical natures and struggles around class, race, and gender. It combines a materialist theory of world-literature with the insights of the world-ecology perspective to generate compelling new readings of writers such as Rhys Davies, Yseult Bridges, Lewis Jones, José Lins do Rego, Ellen Wilkinson, Jorge Amado, Gwyn Thomas, and Ralph de Boissière. The book represents a timely intervention into a series of recent, field-defining debates around peripheral realisms and modernisms, ecocriticism, and the energy humanities.