Graduate students began collecting signatures yesterday for a letter protesting the University’s decision to deny tenure to Associate Professor of Japanese History Mikael S. Adolphson, a leading scholar of pre-modern Japanese history.

The petition, which included the names of roughly 50 undergraduate and graduate students as of last night, calls into question Mass. Hall’s commitment to pre-modern Japanese studies.

The letter seeks “not only to laud the professor’s qualities as a teacher and mentor, but to make a case for the field of Japanese pre-modern history and its relevance to contemporary times.”

Jeremy A. Yellen, a first-year graduate student in the PhD program in modern Japanese history, said that all areas of Japanese studies will “take a hit” when Adolphson leaves Harvard.

“Even those who come here to study modern Japanese history come here because of Harvard’s strength in the pre-modern era,” Yellen said.

Jeffrey Y. Kurashige, a third-year graduate student in pre-modern Japanese history who spent the day gathering signatures, said that the tenure denial seems to indicate that the University is not interested in Adolphson’s field.

“The message this decision sends to academia as a whole is that Harvard doesn’t value history before contact with the West,” Kurashige said.

Interim President Derek C. Bok, whose office holds the final say on University tenure decisions, declined to comment yesterday on Adolphson’s case. Bok has said previously that publicly discussing tenure decisions would be “unpleasant” for the candidate and “unfair” to the professors involved in the process.

A dozen professors either declined to speak about Adolphson’s situation or did not return requests for comment last night.

Adolphson will have to leave the University after his contract ends next spring.

Iman Khosrowpour, a third-year graduate student who drafted the letter, said that Adolphson “should have tenure because we think he’s the best in his field, not only as a scholar but as a mentor.”

“At this point in Japanese historical scholarship,” Khosrowpour added, “there’s nobody more active in the field.”

Both Khosrowpour and Kurashige praised Adolphson for his ability to recruit students to the field and his innovative teaching techniques.

Adolphson, Khosrowpour said, spearheaded the creation of a freshman seminar that takes students on a University-funded trip to Kyoto, Japan.

Adolphson also teaches Historical Study A-14, “Japan: Tradition and Transformation,” and a new course, Japanese History 220, “Warriors, Monks, and Courtesans: Class and Gender Perspectives on Premodern Japan.”

In the past decade, Adolphson has authored two books, “The Gates of Power: Monks, Courtiers, and Warriors in Premodern Japan,” which was published in 2000, and “The Teeth and Claws of the Buddha: Monastic Warriors and Sohei in Japanese History,” which came out this year.

Kurashige said the University’s decision runs counter to the nation-wide trend of enhancing college programs in pre-modern Japanese studies.

“If Harvard is phasing out this sort of program, it’ll send a message to a whole lot of other universities that the study of pre-modern Japanese history is not important,” he said.

—Staff writer Johannah S. Cornblatt can be reached at jcornbl@fas.harvard.edu.