How did increasing aridity after about 1275 affect Plains Village cultures?

The period of increasing aridity that began around 1275 significantly disrupted the established Plains Village cultures, which had previously thrived during a time of favorable agricultural conditions. This climatic shift caused widespread hardship and, in some instances, led to armed conflict among these groups as resources became scarce.1

The severity of this period is evidenced by archaeological findings, such as the early 14th-century Crow Creek site in South Dakota, where nearly 500 individuals were killed violently and interred in a mass grave. In response to these difficult conditions, some village-dwelling communities were able to sustain themselves, while others chose to retreat eastward, returning to their traditional lands only after the climate had improved.1