Dave Frohnmayer in 2007. (Paul Carter/AP)

Dave Frohnmayer, an Oregon Republican who served three terms as attorney general in the 1980s and spent 15 years as president of the University of Oregon, died March 9 at his home in Eugene, Ore. He was 74.

The cause was prostate cancer, his family announced.

Mr. Frohnmayer served in the state legislature before he was elected attorney general in 1980. He ran for governor in 1990 but lost in a three-way race to Democrat Barbara Roberts.

Mr. Frohnmayer represented an old-school strain of Republican politics in Oregon, marked by moderation and liberalism in figures such as Gov. Tom McCall and U.S. Sen. Mark O. Hatfield that has been eclipsed in an era of sharper partisan differences.

After his career in elective office, he went to the University of Oregon, where he served as dean of the law school and then as president of the university starting in 1994.

During that time he fought to restore dwindling state funding, enlisted the university in efforts to battle climate change, supported American Indian students building a longhouse on campus and adopted the “O” logo made famous by the football team for the entire university. He also lost a feud with Nike founder and UO athletics mega-donor Phil Knight over the athletic apparel company’s labor practices.

As state attorney general in the 1980s, Mr. Frohnmayer prosecuted followers of Indian guru Bhagwan Shree Rajneesh as they tried to establish a political power base on a commune outside the tiny high desert community of Antelope. At the time, authorities said his efforts earned him a spot on the group’s hit list.

Mr. Frohnmayer was born July 9, 1940, in Medford, Ore. He graduated from Harvard University in 1962 and attended the University of Oxford in England as a Rhodes scholar. He received a law degree from the University of California at Berkeley in 1967.

He and his wife, Lynn, started a foundation to combat Fanconi anemia after the rare genetic blood disorder proved fatal for two of their daughters.

In addition to his wife, Mr. Frohnmayer is survived by three children; a sister; and a brother, John, a former director of the National Endowment for the Arts and independent candidate for U.S. Senate.