[2] She serves as the Walter S. and Lucienne Driskill chair in Western American History at University of Colorado-Boulder.

Fenn originally planned to write her dissertation on millenarianism in Native American culture, but left her doctoral program at Yale before it was finished, as she was "bored" with academia.

Pox Americana, her dissertation about the 1775–82 North American smallpox epidemic, was written while working part-time, and completed in 1999.

[4] Fenn was interviewed on multiple national news outlets about biological warfare after the September 11 attacks.

[5] Fenn won the 2004 Cox Book Prize for her work Pox Americana: The Great Smallpox Epidemic of 1775-1782.