Trained as a social and political historian, I have focused most of my research on the history of indigenous peoples in North America and their relations with European settlers and their governments.  I came to Illinois from the Newberry Library where I served for fifteen years, first as Director of the D'Acry McNickle Center for American Indian History and later as Vice President for Research and Education.  At the Newberry I developed programs for scholars, students and teachers that promoted the study of the Native American past and administered an internationally-acclaimed fellowship program for scholars in all fields.  These programs were supported by the Ford, Mellon and Rockefeller foundations, the National Science Foundation, and the National Endowment for the Humanities.  At Illinois I teach courses in Native American history as well as other offerings for graduate and undergraduate students.  I have taught at Antioch College adn Northwestern University and am the recipient of honorary degrees from Amherst College (1994) and Long Island University (2000). In 2013 I was elected to the American Academy of Arts and Sciences.

Throughout my career I have also maintained a role as a public historian. I have been a consultant and expert witness for the U.S. Department of Justice, the U.S. Senate Committee on Indian Affairs, the National Congress of American Indians and the National Park Service.  I have also been President of the American Society for Ethnohistory and a member of the Executive Council of the Organization of American Historians.  I have served on the governing boards of Amherst College and the Illinois Humanities Council and was a founding trustee of the Smithsonian Institution's National Museum of the American Indian. My research has been supported by fellowships from the Rockefeller and Mellon Foundations, the National Endowment for the Humanities, and the Huntington Library.