Archaeological evidence is combined with 17th-century documents to record the production of red stone beads by Anishinaabe communities in southern Ontario for exchange with neighboring Iroquoian populations as far away as the Seneca in upstate New York. A transition from local red siltstone to exotic catlinite appears to have been influenced by the mid-century Iroquois Wars, while the symbolism inherent in these items may have been related to the introduction of European diseases.