Yaupon (the unfortunately named Ilex vomitoria) is a holly commonly used as yard décor in the southeast United States, but many North Americans will be surprised to learn that it is the source of a stimulant tea that has been in continuous use for nearly a millennium. Yaupon is more than a drink; it is a window into questions of identity, community belonging, and how the New World was inserted into the global economy. From Cabeza de Vaca's sixteenth-century brush with the beverage, yaupon has iterated between ceremony, medicine, and caffeinated tea as inhabitants of North America—Indigenous, enslaved, and settler colonial inhabitants of North America—have harnessed the leaf's properties to different, culturally situated aims. This article traces narratives, recipes, and medical descriptions of yaupon from contact to the present, and compares these against material and archeological records to explore differences between settler and extractive colonial encounters with Indigenous psychoactive substances (and thus indigeneity). The story of yaupon reveals contests between regimes of knowledge, the political economy of colonialisms, and the fraught intersections of identity and cuisine. Despite abundant ethnographic, documentary, and scientific evidence to the contrary, the scientific and medical literature long mislabeled yaupon as emetic. This raises questions about how knowledge is transferred and how scientific authority is constructed. I argue that indigeneity, race, and class have steered how yaupon has been understood, and help to explain why a popular caffeinated product waned at a time when the use of stimulants was increasing, and “proletarian hunger-killers” were on the rise.