Steven Muller, president of John Hopkins University poses for a portrait in this file photo on the Baltimore, Md. campus on December 23, 1988. (Carol Guzy/The Washington Post)

Steven Muller, a former president of Johns Hopkins University who led the institution through a period of unprecedented growth in the 1970s and ’80s, died Jan. 19 at his home in Washington. He was 85.

His death, from respiratory failure, was confirmed by his wife, Jill E. McGovern.

Known during his long tenure at Hopkins as one of the most powerful academic administrators in the United States, Dr. Muller brought a background of accomplishment and a wealth of experiences to the post. He was a refu­gee from Nazi Germany, a child actor in Hollywood and a Rhodes scholar. During the 1960s, before coming to Baltimore, he helped defuse one of the most prominent of campus protests.

A scholar in the field of comparative government, he joined Johns Hopkins in 1971 as provost and became president the following year. His tenure of 18 years was more than three times as long as that of the average university president of his era. He headed Johns Hopkins longer than anyone since Daniel Coit Gilman became its first president in 1875.

During the first 10 years of his tenure, Dr. Muller assumed an unusual double role and served as president of Johns Hopkins Hospital. The hospital is one of the most prestigious medical facilities in the United States, and Johns Hopkins University is widely known as one of the top research institutions.

When Dr. Muller assumed the presidency in 1972, Johns Hopkins was recovering from budget shortfalls that had stricken many U.S. universities at the time. Known for boardroom charisma and fundraising skill, he oversaw two major development drives.

The first, in the 1970s, raised more than $109 million for the university and hospital; the second brought in $600 million, exceeding the stated goal by a third. Meanwhile, the budget swelled six-fold, The Washington Post reported at the time.

The expansion overseen by Dr. Muller transcended academic disciplines. In 1981, Johns Hopkins was chosen over other prestigious institutions as the site of the Space Telescope Science Institute — the entity that runs the science program for the Hubble Space Telescope. The building that houses the institute is named for Dr. Muller.

Dr. Muller also was credited with expanding the physics, astronomy, engineering and nursing programs, as well as supervising the growth of what is now the Johns Hopkins Bayview Medical Center.

In the humanities, he helped connect Hopkins with the storied Peabody music conservatory. In foreign affairs, he helped create satellite campuses in China and Italy.

But by the end of his tenure, Dr. Muller began to encounter resistance from professors and administrators in the humanities programs, some of whom argued that his expansion initiatives distracted the university from core programs in the liberal arts.

Despite overall gains in fundraising, the poor stock market performance of the 1980s left the university with financial problems. Some academic programs, particularly in the humanities, remained underfunded. The School of Arts and Sciences had an $8 million deficit in 1989.

That year, Dr. Muller announced that he would step down in 1990. “From my point of view, it is better to pick an appropriate time to leave and move on to something else than to sit around and fade into some kind of twilight,” he said.

After his retirement, he served for a number of years on the board of trustees of St. Mary’s College of Maryland, including a stint as chairman.

Only at the end of his career did he begin to speak publicly about his childhood in Germany.

Stefan Mueller was born Nov. 22, 1927, in Hamburg. His father, a lawyer, was Jewish; his mother was Catholic.

In the 1930s, as the Nazis gained strength, Dr. Muller was attacked by former friends who had become members of the Hitler Youth. Until the end of his life, he had physical scars from the beatings, Washington Jewish Week reported.

His father was rounded up in a sweep of Jewish men on Kristallnacht, or the “Night of Broken Glass,” in 1938 and incarcerated. Upon his release, he left for England and was followed by his family. As a boy, Dr. Muller lived for a time with a British couple who helped him learn perfect English.

In 1940, the Muellers arrived in the United States, where Dr. Muller changed his name to Steven Muller. The family later settled in Los Angeles, where the father ran a candy shop and Dr. Muller sold the Saturday Evening Post on the street.

One day, a client identified himself as a Hollywood screenwriter and offered to introduce the young Dr. Muller to moviemaking. He appeared in seven films in the early 1940s, including “The White Cliffs of Dover.”

The films brought the family substantial and much-needed income, his wife said.

Dr. Muller ultimately chose higher education over Hollywood. He received a bachelor’s degree in political science from the University of California at Los Angeles in 1948 and studied politics at Oxford University in England as a Rhodes scholar from 1949 to 1951. After serving in the Army Signal Corps, he received a doctorate in comparative government from Cornell University in Ithaca, N.Y., in 1958.

Dr. Muller taught government at Haverford College in Pennsylvania and Cornell University before moving into administration. At Cornell, he became director of a center for international studies and vice president of public affairs before moving to Johns Hopkins.

During the racial turmoil afflicting campuses throughout the country in the 1960s, he negotiated an amnesty agreement to end an occupation of the student union by armed African American students.

His wife of 48 years, Margie Hellman Muller, died in 1999. Survivors include his wife of 13 years, Jill E. McGovern of Washington; two daughters from his first marriage, Julie M. Mitchell of San Francisco and Elizabeth M. Casparian of Princeton, N.J.; a brother; and five grandchildren.

In an interview with Washington Jewish Week, Dr. Muller compared Hollywood to academia.

“My role as Johns Hopkins president,” he said, “was the biggest and best ‘part’ I had ever played. I always had to be onstage.”