New York University (NYU) Associate Professor of History Walter Johnson—maven of 19th century history on slavery, capitalism, and imperialism—will trade the Big Apple for the Big Dig when he comes to Harvard next month as one the newest tenured professors in the Department of History.

Johnson, 39, will become one of the youngest tenured faculty in his department, reflecting a broader trend “to look for our tenure level hiring toward scholars just coming into prominence at earlier points in their careers than has been typical for Harvard,” according to History Department Chair Andrew D. Gordon ’74.

Gordon added that the department’s last two external hires, Daniel L. Smail from Fordham University and Henrietta Harrison from Leeds University, also reflect the recent trend of appointing younger faculty—a practice encouraged by both former University President Lawrence H. Summers and former Dean of the Faculty William C. Kirby.

Upon his arrival in August, Johnson will begin gearing up for his two fall courses. His introductory level lecture course, entitled “Empire of Liberty,” will re-examine 19th century United States history in a broader international context, beginning with the War of 1812 and wrapping up with the 1898 Spanish-American War.

Gordon said this course could potentially be a part of the Core curriculum and satisfy the Historical Studies B requirement or qualify as a departmental equivalent. Johnson last taught the class at NYU during fall 2005.

Johnson will also direct a course in September for students beginning the doctorate program in American Civilizations at the Graduate School of Arts and Sciences.

Gordon said that Johnson’s scholarship will add to the department’s small group of faculty specializing in slavery, which includes Associate Professor of African and African American Studies Susan O’Donovan and Assistant Professor of History Vincent Brown.

“Put that all together and it’s a really great group of scholars,” Gordon said.

Johnson published his first book—”Soul by Soul: Life Inside the Antebellum Slave Market”—about the inner workings of 19th century slave markets. The piece, for which Johnson garnered multiple awards, is a “pioneering study” that draws upon the slaves’ own narratives to divulge the strategies they used to manipulate the market, Gordon said.

Johnson’s current project is a forthcoming book about the history of the Mississippi Valley between the Louisiana Purchase and the Civil War. The work traces the spread of slavery through the Mississippi delta, Gordon added.

After reviewing Johnson’s works and receiving recommendations from colleagues, Gordon said he “saw the opportunity to bring in somebody outstanding,” who was not already on the history department’s regular roster of upcoming appointments.

In an evaluation process that ran the duration of the last academic year, Johnson was compared with half a dozen other candidates competing for tenure, according to Gordon. He was invited to give a lecture at Harvard last year that members of the department critiqued.

“He was the one that was in our sights from the start,” Gordon said. “Across the board we expect him to play a really important role,” Gordon said.

Johnson was offered the appointment in late February and officially delivered his acceptance last month.

Johnson graduated from Amherst College with high honors and a bachelors degree in history in 1988 and attended the University of Cambridge’s post-graduate program immediately thereafter.

He later received a doctorate in American History from Princeton University and was appointed assistant professor of history at NYU. Johnson received a promotion to associate professor in 2000 and was most recently director of the univesity’s American Studies Program.

Johnson relocate to Cambridge next month with his wife and two children—ages four and six.

“I’m not looking forward to moving, but I’m looking forward to being moved and getting going teaching,” he said.

—Staff writer Ying Wang can be reached at yingwang@fas.harvard.edu.