Nheengatu was a linguistic framework created by Jesuits to facilitate Catholic catechism in the Portuguese Amazon. This language eventually transcended the evangelization, spreading across indigenous villages, reaching Africans and their descendants who began to arrive in large numbers through the ports of São Luís and Belém in the mid-18th century. The language became commonplace in workplaces across the rainforest, enduring through centuries and persisting in Amazonian daily life after the independence of Brazil. This article discusses some aspects of this dialect’s use among subalternized populations, particularly runaway slaves in the 19th century.