This article sheds light on the issue of agency in the making of world Christianity at the level of theological discourses. Within a wider context of persistent paternalism, British Brethren missionaries progressively released leadership to local Latin Americans, in large part due to their congregational polity, which lacked paid clergy and hierarchy. The Brethren tradition of pioneering publishing projects created channels through which Latin American evangelicals wrote their own theologies and developed a new brand of Protestant social Christianity. This allowed Latin American Protestant evangelicals to diffuse social Christian ideas to a wider constituency. Thus, while Christian Brethrenism provided raw ingredients for the fundamentalist movement in the north, it should also be credited with providing a perceived escape hatch from it in the south. This article breaks fresh ground by paying particular attention to unstudied personal papers, archival documents, and bilingual interviews with many of the main players.