Food insecurity and the disruption of agricultural systems are often cited as explanations for the correlations observed between climate change and demographic shifts in past agricultural societies. While these narratives are abundant with data pertaining to climate and demographic changes, they often lack substantial information regarding the processes contributing to agricultural destabilization. In this article, we employ stable carbon isotopes extracted from paleosols collected at Cahokia Mounds, the largest Indigenous settlement in North America, to illustrate that vegetative communities did not respond to the multi-decadal drought that afflicted the mid-continent region at the end of the 13th century. This research underscores the existing gaps in our understanding of how plant communities respond to climate variations. To effectively utilize historical examples in shaping future strategies for adapting to contemporary climate change, it is imperative that we acquire deeper insights into the tolerance of Indigenous crops and culturally significant plants to various drought and flood conditions.