Louis Headman (Ponca elder) is the senior language researcher for the Ponca Tribe of Native Americans, project coordinator of the Ponca Language Grant, and pastor at the Church of the Nazarene in Ponca City. He is the author of Walks on the Ground: A Tribal History of the Ponca Nation (Nebraska 2020). Sean O’Neill is an associate professor of anthropology at the University of Oklahoma. He is the author of Cultural Contact and Linguistic Relativity among the Indians of Northwestern California and the coeditor of The Collected Works of Edward Sapir: Northwest California Linguistics, vol. 14.