Pekka H�m�l�inen is Associate Professor, Borderlands and Native American History, University of California, Santa Barbara. He received his Ph.D. from the University of Helsinki in 2001. He is the author of WHEN DISEASE MAKES HISTORY: EPIDEMICS AND GREAT HISTORICAL TURNING POINTS (Helsinki University Press, 2006) and THE COMANCHE EMPIRE (Yale University Press, 2008), which won the Bancroft Prize.