A senior research fellow at the Robert H. Smith International Center for Jefferson Studies at Monticello and Thomas Jefferson Foundation Professor of History Emeritus at the University of Virginia, Peter S. Onuf has written extensively on sectionalism, federalism, and political economy, with a particular emphasis on the political thought of Thomas Jefferson. With his brother, political theorist Nicholas G. Onuf, he collaborated on Nations, Markets, and War: Modern History and the American Civil War (2006), a history of international law and order in the Atlantic states' system during the Age of Revolutions and early nineteenth century. He is also the author of The Mind of Thomas Jefferson (2007) and a coauthor, with Annette Gordon-Reed, of "Most Blessed of the Patriarchs": Thomas Jefferson and the Empire of the Imagination (2016). His new book, "Jefferson and the Virginians: Democracy, Constitutions, and Empire," is forthcoming. An elected member of the American Academy of Arts and Sciences, he is also a founding cohost of the public radio program and podcast BackStory.