Markus Wolf, who outwitted the West as communist East Germany's long-serving spymaster, died Thursday at the age of 83.
Wolf died in his apartment in Berlin, his stepdaughter Claudia Wall said in a statement. The cause of death was not released.
Known among rival spies as "the man without a face" for his elusiveness, Wolf planted some 4,000 agents in the West — most famously, placing Guenter Guillaume as a top aide to West German Chancellor Willy Brandt. The agent's unmasking forced Brandt to resign in 1974.
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Wolf, who said he spurned a CIA offer of a safe new life in California after the Cold War, managed to steal NATO secrets for the Soviet bloc that could have been decisive if war had broken out in Europe.
Born Jan. 19, 1923, in the southwestern town of Hechingen, Wolf and his family followed his father — a Jewish communist, doctor and writer — into exile in France in 1933 after the Nazis came to power.
The Wolfs moved to the Soviet Union in 1934, and the young Markus studied aeronautical engineering in Moscow before being sent for political training at a Communist International, or Comintern, school in the Bashkiria region.
He worked at German People's Radio in Moscow from 1943 to 1945, when he returned to Germany with a group that included Walter Ulbricht, who would become East Germany's longtime leader.
After reporting from the Nuremberg war crimes trials of Nazi leaders and returning to Moscow for a time as a counselor at the fledgling East Germany's embassy, Wolf joined the new communist state's embryonic foreign intelligence service in 1951. He became its leader the following year, and stayed in the job until his retirement in 1986.
Wolf's service was part of East Germany's all-pervasive secret police, the Stasi, or Staatssicherheit, which was widely loathed and feared for its huge network of domestic informants. Wolf served under Erich Mielke, the hated Stasi chief, from 1956 until the fall of the Berlin Wall.
Western agencies didn't know what the East German spy chief looked like until 1978, when he was photographed during a visit to Sweden. An East German defector, Werner Stiller, then identified Wolf to West German counterintelligence as the man in the picture.
Some also believe Wolf was the model for John Le Carre's wily communist spymaster "Karla" in his espionage novels.
The Stasi — which at home enlisted spouses and lovers to spy on their partners — sent seductive "Romeo" agents to the West to steal secrets from lonely government secretaries.
Wolf said in his memoirs that "if I go down in espionage history, it may well be for perfecting the use of sex in spying."
Wolf said his first "Romeo," an engineering student code-named Felix, started work in 1952 and operated under the cover of a traveling shampoo salesman.
He struck up a friendship with a secretary in West German Chancellor Konrad Adenauer's office at a Bonn bus stop; the relationship lasted for several years until East Berlin was tipped off that West German authorities were running a security check on the agent and hastily withdrew him.
Wolf, detailed a string of such sagas in his 1997 book "Memoirs of a Spymaster."
"It was wrong," he told reporters as he promoted the book. "Nobody has the right to spoil an innocent person's life."
Wolf emerged as a supporter of reforms as East Germans took to the streets to press for change in the fall of 1989.
A few days before the Berlin Wall fell, he drew applause at a pro-democracy rally in East Berlin when he denounced violent police attacks on earlier demonstrations.
In May 1990, with German reunification approaching, Wolf said two men appeared at his dacha near Berlin with an offer from then-CIA director William Webster to work for the U.S. spy agency.
One of the two was Gardner Hathaway, who had just retired as assistant CIA director for counterintelligence, Wolf said. They offered a "seven-figure sum," a new identity and a house in California.
Wolf said he turned down the offer because he would never have betrayed his ex-agents — even though it would have put him out of the reach of German prosecutors, who were seeking him for espionage, treason and bribery.
Later in 1990, Wolf fled to Moscow. With Bonn pressing for his return, he unsuccessfully sought political asylum in Austria and then surrendered to German authorities at a rural border crossing in Bavaria.
In the years of legal wrangling that followed, Wolf avoided lengthy prison time.
A 1993 conviction and six-year prison sentence was overturned in 1995 by an appeals court. It ruled that Wolf was acting on behalf of a sovereign country, East Germany, and could not be tried for treason against West Germany.
In a second trial, Wolf was given a two-year suspended sentence in 1997 for four kidnappings carried out by his agents during the Cold War.
A stony-faced Wolf listened as the judge branded him an accomplice in "state-ordered crimes" against "helpless victims."
Wolf is survived by his wife, Andrea, three sons and his step-daughter. Wall said he would be buried in the presence of only his closest relatives, on a date that was not released.