Damrosch noted that Guillary, a graduate student at Yale during the "great days" of its English department in the '70s, was in his mid-40s--unusually young for a senior Faculty member.

"We're trying to get younger people than the standard full professor. Because the Harvard tenure process is so difficult, the people in their 40s who should be the backbone of the department aren't here," Damrosch said, noting that tenured Faculty were usually accepted in their 50s. "Guillary can help bridge that gap."

Ending a long search for a modern American historian, the history department also offered tenure to Elizabeth Cohen, a professor at New York University (NYU).

"It's a good appointment," said Donald H. Fleming, Trumbull professor of American history at Harvard. "We badly need a professor of the political history of the 20th century United States."

Cohen, a historian of the 20th century, has previously held positions at Carnegie Mellon University and NYU, two "very diffuse" urban campuses, and said she looked forward to Harvard's "collegiality."

At Carnegie Mellon and NYU, "I haven't been able to get to know many of my undergraduates or my fellow Faculty in other fields," Cohen said in a telephone interview yesterday. "I was attracted to Harvard students, I like Cambridge and I'm attracted to a more residential college experience."

Cohen has published two books in recent years on Chicago workers in the New Deal, and "the politics of consumption in post-war America."

"My appointment is part of a commitment of the administration to build on the side of the American history field," she said. "I'm very appreciative about how committed the department is to my field."

Cohen said she planned to offer American history courses including seminars and focused surveys on the '20s, '30s and the New Deal era.

"My guess is that I'll have classes with more than just history concentrators, just because of the nature of the field," she said.

--Georgia N. Alexakis contributed to the reporting of this article