His research examines early modernity, Christianity, and the thought of Niccolo Machiavelli. His current project examines Machiavelli's creative appropriation of history to further his project. Parsons has teaching interests in the broad history of political thought, from ancient political thought to late modernity, including American political thought.

He is the author of Machiavelli’s Gospel: the Critique of Christianity in the Prince (University of Rochester, 2016) and several articles on the history of political thought.

Parsons has a B.A. from the University of Maine and an M.A. and Ph.D. in Political Science from the University of Toronto. Before joining Duke University, he was a faculty member at Duke Kunshan University (tenured), Carroll College (tenured) and James Madison University (visiting).