T. Marshall Hahn Jr., who as president of Virginia Tech transformed it from a regional military college with a mostly white, mostly male student body into a diverse, internationally renowned research university, died on May 29 at his home outside Blacksburg, Va. He was 89.

The university, in Blacksburg, announced the death.

In 1998, in a retrospective examination of Dr. Hahn’s career, The Roanoke Times called him “the man who made Tech what it is today.”

A physicist by training, Dr. Hahn assumed the presidency of Virginia Polytechnic Institute, as it was then known, in 1962. At the time, enrollment numbered not much more than 6,000.

Although students at the institute’s associated women’s college, Radford College (now Radford University), could attend courses at Virginia Polytechnic, the student body was nominally all male. And though the institute had admitted its first black student in 1953, it remained overwhelmingly white.