The depopulation of the St. Lawrence River Valley by Iroquoian-speaking people has long fascinated archaeologists in northeastern North America. This departure had profound effects on surrounding Indigenous societies and ultimately opened the St. Lawrence River to European colonization in the seventeenth century. As the story goes, between 1450 and 1580, St. Lawrence Iroquoians were attacked and assimilated by their Huron-Wendat and Haudenosaunee neighbors over competition for European objects. Though there is little archaeological evidence to support this narrative, it has remained at the center of many scholarly discourses on the matter. In this paper, I use recently published radiocarbon timelines from southern Ontario and New York State alongside material proxies for St. Lawrence Iroquoian movement to explore the relationship between the timing of Iroquoian movements away from the St. Lawrence Valley, the emergence of inter-regional conflict, and the onset of European trade. I contend that any honest and accurate understanding of the factors driving depopulation must be contextualized within Iroquoian social and historical developments. These developments preceded depopulation and the beginnings of European trade by over a century and continued to influence Iroquoian relationships to the St. Lawrence Valley well after 1580.