Former West German chancellor Willy Brandt, one of the most towering actors to stride across the European stage in the postwar era, died last night at his home near Bonn after a long battle with intestinal cancer. He was 78, and had rejected a third operation.

"Germany has become a poorer place," the German national radio station Deutschlandfunk said this morning. "No German statesman of the postwar era enjoyed as high a reputation abroad as Willy Brandt."

During the 1970s, it was Brandt who established the agenda for the events that ultimately would lead to the liberation of Eastern Europe and the reunification of Germany.

"His biography is virtually a distillation of the 20th century," historian Arthur M. Schlesinger Jr. once said of Brandt. "It is odd to see how this unassuming fellow from Luebeck managed to incorporate in one life so many of the great themes of this turbulent time."

Schlesinger was referring to a career that began with Brandt's youth as a Socialist street fighter battling Nazi storm troopers in 1930s Germany and that continued after World War II when, as governing mayor of West Berlin, he headed the resistance to efforts by the Soviet Union and East Germany to use the Berlin Wall to choke off the city's ties to the democratic West.

But Brandt's most historic role began in 1969 when he led his Social Democratic Party to power in West Germany and, as chancellor, launched the diplomatic initiative that forever will be associated with his name. That was the Ostpolitik, or Eastern policy, aimed at establishing an atmosphere of detente within Europe through gradual, step-by-step overtures of friendliness and cooperation with the Soviet Union and the Eastern bloc.

{News of Brandt's death broke early this morning in Berlin, the city he served as mayor for nine years, correspondent Marc Fisher reported from the German capital. In the all-night bars on Grolmanstrasse, Berliners said Brandt was the first person after World War II to make many Germans comfortable with the very concept of political leadership.

{"He's the only chancellor in my lifetime I would ever have wanted to meet," said Wolf Kuhn, a 44-year-old business manager.

{Brandt lived at home during the final months of his illness. He received guests until late last month, when Chancellor Helmut Kohl dropped by for an extended talk. But by the beginning of this month, Brandt's condition had deteriorated to the point that when former Soviet leader Mikhail Gorbachev drove up to his house for an unannounced visit, he was turned away at the door.}

A White House spokesman last night called Brandt "a historic figure and European leader . . . widely respected in the U.S. It was particularly significant that he lived to see his country unified and the realization of his dream of harmony between East and West."

Brandt's Ostpolitik was based on the assumptions that the division of Europe into opposing ideological blocs was permanent, that the two sides had to find a way to live with each other if they were to avoid war and that easing Moscow's fears of a resurgent Germany was the key to establishing this coexistence.

These ideas probably seem naive and beside the point to a younger generation that in the past three years has seen the Cold War evaporate with the disappearance of East Germany, the liberation of Moscow's other former East European satellites and the breakup of the Soviet Union.

However, two decades ago, no one had any idea that communism was heading for collapse before the century had run its course. On both sides of the Atlantic, the Soviet Union was regarded unquestioningly as a nuclear superpower with total control over its half of Europe.

Brandt's introduction of his Ostpolitik at a time when East-West relations were in a deep freeze because of the 1968 Soviet intervention in Czechoslovakia was of major historical importance because it marked the first sustained effort to start chipping away the ice of the Cold War.

It was an approach that provoked fierce resistance from conservative political opponents in Germany. It also caused great anxiety among inveterate cold warriors in Washington, who feared that it would weaken the Atlantic Alliance by drawing Germany away from the anchor in Western Europe established by his predecessor, Konrad Adenauer, and move it toward neutralism.

In retrospect, though, it is clear that the Ostpolitik had the opposite effect -- that it was the prologue to the breathtaking events that shaped Europe in subsequent years.

It opened the way for Washington and Moscow to begin grappling in earnest with disarmament. It gave Western Europe a lengthy period of calm in which to accelerate the movement toward European unity. And, most importantly, by opening some windows to the West, it kept alive the spirit of reform within the Soviet Union and Eastern Europe that led eventually to the fall of the Communist empire.

That Europeans on both sides of the ideological divide were ready for such an initiative became evident with Brandt's very first foray into Ostpolitik. In March 1970, he traveled to the East German city of Erfurt to discuss normalizing relations between the two Germanys with East German Premier Willi Stoph.

'Willy, Willy'

From the moment he set foot in Erfurt, a shout of "Willy" erupted from thousands of East Germans who had gathered to see him. Then, the cheering halted abruptly, as people realized that the cries of "Willy" might be interpreted as cheering Stoph. A moment later, it began again, although this time as a rhythmic chant of "Willy, Willy, Willy Brandt!" that cascaded through the streets and followed him without letup wherever he went in Erfurt.

Erfurt was the start of a dizzying chain of events that in ensuing weeks made Brandt the most closely observed leader in Europe. In August 1970, following extended negotiations, he and the collective Soviet leadership led by Leonid Brezhnev gathered under glittering crystal chandeliers in the grand Catherine Hall of the Kremlin to sign a nonaggression treaty designed to avert repetitions of the two world wars that had stained the soil of Europe with massive bloodshed.

The two powers agreed never to use force against each other, to renounce territorial claims against other countries, and to recognize the inviolability of all boundaries, including the border between East and West Germany and the Oder-Neisse line, which had been established as Poland's western frontier.

That amounted to recognizing the division of Germany and the loss of thousands of miles of German territory that had been incorporated into Poland and the Soviet Union at the end of World War II. The treaty met with opposition in Germany so furious that it took two years to win ratification from the West German parliament. But Brandt ultimately prevailed by refusing to waver from the argument he made in Moscow at the time of the treaty signing.

"Nothing has been lost here that was not gambled away long ago by the evil Nazi regime," he said.

In December 1970, Brandt journeyed to Warsaw to sign a similar treaty normalizing relations with Poland. The next day, front pages all over the world prominently displayed photographs of the West German chancellor, his lips quivering with emotion, falling to his knees and bowing his head in silent tribute at a memorial to victims of the Warsaw Ghetto.

The attention accorded his missions to Moscow and Warsaw underscored how far Brandt had come since his illegimate birth as Herbert Ernst Karl Frahm in the old Baltic seaport of Luebeck on Dec. 18, 1913. His mother was a shopgirl, and he never knew his father.

As a youth, he became a believer in the doctrines of socialism, and while a teenager became the protege of Julius Leber, a leader of the Social Democratic Party who later would be executed by the Nazis as one of the chief instigators of the abortive 1944 plot to kill Hitler. At the outset of the 1930s, when the specter of National Socialism began to appear in Germany, Frahm joined other young socialists in street brawls against Nazi brownshirts and contributed anti-Nazi articles to newspapers under the name of "Willy Brandt."

After the Nazis came to power in 1933, Frahm -- now formally calling himself Willy Brandt -- fled to Norway, where he established himself as a journalist. When the Germans invaded Norway in 1940, Brandt, a soldier in the Norwegian army, was taken prisoner, although he subsequently managed to escape to neutral Sweden, where he spent the rest of the war.

Years later, after he had entered German politics, his opponents frequently used both his illegimate birth and the fact that he had fought against Germany in an effort to discredit him with voters.

In 1946, Brandt, by then a major in the Norwegian army, returned to a defeated Germany as press attache of the Norwegian military mission in Berlin. He was then a Norwegian citizen and had been offered the opportunity of a career in the Norwegian diplomatic service. But, after much agonizing, he decided that he had an obligation to help with the rehabilitation of his native land. He resumed his German citizenship, renewed his ties with the German Social Democrats and became an aide to Ernst Reuter, the mayor of West Berlin at the time of the Berlin airlift.

In November 1956, Brandt vaulted to the forefront of national attention when he averted a bloodbath by singlehandedly stopping thousands of West Berliners from storming into East Berlin to protest the Soviet invasion of Hungary. The episode was instrumental in his being elected mayor the following year. In that position, he became famous throughout the world as the symbol of embattled West Berlin, a Western enclave 150 miles inside the Communist East.

At the same time, Brandt was rising steadily to the leadership of the Social Democratic Party and was a prime mover of the party's 1959 decision to jettison much of its doctrinaire Marxism and recast itself in the mold of liberal democracy with respect for private property and a free-market economy.

However, German voters initially were reluctant to accept the Social Democrats' new image and turn away from the conservative Christian Democrats who had held power since the restoration of self-government in 1949. Twice during the 1960s, Brandt's bids to become chancellor were rebuffed by the electorate.

Then, in 1966, the Social Democrats, in a calculated effort to show that they could be trusted to hold office, agreed to become junior partners in a coalition with the Christian Democrats. Brandt, serving as vice chancellor and foreign minister, launched his first tentative probes toward the east.

Election Victory

His performance made him the star of the coalition's cast, and when new elections were held late in 1969, he finally succeeded in leading the Social Democrats to control of the government for the first time in the party's history.

That started the whirl of dipomatic activity that took him to Moscow, Warsaw, other East European capitals and, in December 1971, to Oslo, where he became the first German of the postwar era to receive the Nobel Peace Prize.

Yet, while Brandt then was unquestionably the most famous and most respected German in the world, his position at home was becoming insecure. His preoccupation with foreign policy had caused him to neglect domestic issues, including the rising tide of inflation and the oil price shocks caused by the 1973 energy crisis.

He prevailed over the Christian Democrats in the national elections of October 1972. But, as he struggled with economic problems that he found unfamiliar and intractable, the brooding, remote side of his nature became increasingly prominent.

In earlier years, his penchant for heavy drinking had caused Germans to dub him "Willy Weinbrand" after the name of a potent local brandy. And he long had a reputation for womanizing -- a factor that eventually led to his divorce from his Norwegian second wife, Rut. Throughout Bonn in those days, people speculated openly about whether Brandt was reverting to the moodiness that had made many voters mistrustful of him at the outset of his career.

Ultimately he reached a sort of psychological breaking point in 1974 when one of his personal aides, Guenther Guillame, was exposed as a deep-cover East German spy. To the shock of his countrymen, Brandt abruptly resigned the chancellor's office.

He kept the post of Social Democratic Party chairman. But while he held that post for another 13 years and also served as chairman of several prestigious international commissions, his glory days were over. As party chairman, Brandt drifted increasingly toward the left, siding with a resurgent left wing whose neutralist-leaning views on nuclear and defense issues were increasingly at odds with the centrist positions of Helmut Schmidt, Brandt's strong-minded successor as chancellor.

In what many former admirers considered the nadir of his career, Brandt played an important role during the early 1980s in turning the Social Democrats against the deployment of U.S. medium-range missiles in Europe. While such positions caused increasing estrangement from the Schmidt faction of the party, he also was criticized by young Turk leftists for being out of date and clinging to power too long.

Early in 1987, he was forced to resign as party chairman after facing a revolt over what was regarded as his high-handed attempt to give the job of party spokeswoman to a young Greek woman, who was a personal friend but not a German citizen. Three years later, on the eve of the Persian Gulf War, Brandt embarrassed the German government by making a controversial, four-day visit to Baghdad, Iraq, where he met twice with Iraqi President Saddam Hussein to obtain the release of several Western hostages.

But not all of Brandt's actions in his later days were embarrassments. Unlike many other leading Social Democrats, Brandt embraced the idea of quickly reunifying the two Germanys. In June 1991, after the German parliament voted to underscore the reunification by moving the capital back to Berlin, crowds of Berliners gathered on the bustling Kurfuerstendamm to take up the old chant of "Willy! Willy!" in gratitude for their old mayor's impassioned support for the move. Brandt himself had made his views clear a year earlier.

"To have contributed to the situation in which the name of Germany, the idea of peace and the prospect of European freedom are thought of together, is the essential achievement of my life," he said.

The Post's Fisher added from Berlin:

Early this year, in his last interview with The Post, Brandt said: "The next 10 to 12 years will be a critical period for Germany. There is no doubt that after that period, what was East Germany will be the more prosperous part of Germany. But it will take time, more time than anyone expected.

"One thing we underestimated is that you have to deal with more than one generation of people who never experienced personal responsibility."