Frederic Pryor, an American graduate student who was jailed in East Germany in 1961 on suspicion of espionage but later freed as part of the famous prisoner trade between the United States and Soviet Union dramatized in Steven Spielberg’s film “Bridge of Spies,” died on Sept. 2 at his home in Newtown Square, Pa. He was 86.
His son, Dan, confirmed the death.
By the summer of 1961, Mr. Pryor had been living in West Berlin for two years. Despite worsening Cold War tensions, he crossed regularly into East Berlin to interview economists and government officials for his doctoral thesis about the foreign trade system of the Soviet bloc.
While the Berlin Wall was being built, Mr. Pryor drove into East Berlin on Aug. 25, 1961. He tried to visit an engineer who had helped him on a research project, but when he reached her apartment, she was gone.
The Stasi, East Germany’s secret police, which had been staking out her home, arrested Mr. Pryor for aiding in her escape to the West. And after they found a copy of the thesis in his car, they charged him with being a spy.
He was confined to a cell that he described as “six paces long by two paces wide”; interrogated nearly every day for most of his time in prison; and informed on by a cellmate who had apparently been planted by the Stasi.
“I wasn’t worried about being brainwashed, and I didn’t think I would be tortured,” he told Michigan Today magazine in 2016, “since whatever ‘crime’ they thought I was guilty of wasn’t very important. I accepted my situation and tried to make the best of it.”
Still, the East German prosecutor in charge of his case was planning to put him on trial and declared that he would seek the death penalty.
Mr. Pryor was unaware of a larger drama involving negotiations to trade prisoners already known as Cold War proxies. Francis Gary Powers was the Air Force pilot shot down over the Soviet Union in 1960 on a U-2 reconnaissance mission for the C.I.A. Rudolf Abel, a K.G.B. colonel, was serving a 30-year prison sentence in a federal prison in Atlanta after being convicted in 1957 of spying by a jury in Brooklyn.
They were the key pieces in the exchange orchestrated by James Donovan, the lawyer played by Tom Hanks in “Bridge of Spies.” Although Mr. Pryor was not a spy, his release was a priority of Mr. Donovan’s.
On Feb. 10, 1962, after nearly six months in jail, Mr. Pryor was driven to Checkpoint Charlie in Berlin and released. The Powers-for-Abel swap occurred at Glienicke Bridge, a border crossing between East and West Berlin.
When he returned to the United States, Mr. Pryor was wearing the same suit he had been captured in. But now its buttons were gone and its fabric threadbare. At a news conference, he told reporters he would not criticize East Germany to score propaganda points.
“After tomorrow,” he said, “forget me.”
Frederic LeRoy Pryor was born on April 23, 1933, in Owosso, Mich., but grew up mainly in Mansfield, Ohio, where his father, Millard, was chairman of the Barnes Manufacturing Company, and later worked with the United States Agency for International Development. His mother, Mary (Shapiro) Pryor, was a journalist before becoming a homemaker.
After graduating from Oberlin College with a bachelor’s degree in chemistry — a subject he came to dislike after spending a summer working for Dow Chemical — Frederic took a year off to travel, living on a commune in Paraguay and working on a freighter to Europe.
The trips initiated his interest in economics, which he studied at Yale, where he earned a master’s degree and the Ph.D. he would receive after leaving East Germany.
Mr. Pryor wanted to work for the government, but his arrest on an espionage charge made him unwanted. At General Motors, where he had been a consultant before his arrest, an official said he would not consider him because of his prison record.
Although he was reluctant to teach, he found academia welcoming. Soon after his release from prison, the University of Michigan hired him to teach economics. He stayed until 1964, when he became a staff research economist at Yale. In 1967, he left for Swarthmore.
He became known mostly for his scholarly research, whether he was comparing capitalism to socialism or examining the economics of agricultural and primate societies.
“The range of his curiosities and interests was wide, and he always put a distinct spin on a debate,” Stephen O’Connell, chairman of Swarthmore’s economics department, said by phone. “He also dove into issues in public policy with papers like one about the geography of hate.”
Mr. Pryor retired from Swarthmore in 1998 but kept an office there and continued his research.
For decades, he preferred to discuss his latest paper to his role in the long-ago Cold War saga. But with the release of “Bridge of Spies” (in which he was played by Will Rogers), Mr. Pryor gave interviews, reflecting on his imprisonment and pointing out errors in the film — for example, its depiction of his being arrested while trying to help a woman and her father escape as the Berlin Wall was rising.
“I enjoyed the movie,” he told Michigan Today. “But the person with my name in the film has nothing to do with me.” He added, “I resent the fact that Steven Spielberg never contacted me to find out what really happened.”
In addition to his son, Mr. Pryor is survived by three grandchildren. His wife, Zora Prochazka, who was also an economist, died in 2008.
All along, Mr. Pryor said he was not a spy. Nothing in his dissertation — with its trade analysis and charts on commodity pricing — could have been construed as evidence of espionage.
“The reader can judge the nature of my ‘spying’ for himself,” he wrote in the preface to the version of his dissertation that was published as a book in 1963, “for this book is essentially the ‘spy document’ which was found in my car upon my arrest.”
He found no complete answers for his arrest in the Stasi’s 5,000-page file on him when he returned to a reunified Germany in the early 1990s.
But he felt queasy as he read about the collusion between his cellmate and the Stasi; an accusation that he had worked for the C.I.A.; and the interrogation strategies used against him.
“I felt again what it was like in my cell and the efforts I took to maintain some mental equilibrium — for instance, trying to remember everyone in my third grade class,” he wrote in The National Interest magazine in 1995.
“In that reading room,” he added, “I began to have difficulties in maintaining my objectivity and I had to remind myself that 31 years had passed since these events took place.”