As Europe prepares for the 40th anniversary of Hitler's defeat, Warsaw's national theater is featuring a play called "Yalta," about the 1945 conference widely thought of as having consigned Poland and the rest of Eastern Europe to Soviet hegemony.

The play's dialogue is authentic, drawn from detailed Soviet, British and U.S. accounts of the week-long Crimean summit, which ended 40 years ago Monday. Against a backdrop of conference photos flashed on the stage, the reenacted conversations provide poignant images of the Big Three deliberating over the fate of Europe.

Amid champagne toasts and clever repartee, some of the major political principles binding postwar Europe were set at the Soviet Black Sea resort, including an agreement on German reparations, plans for control of a soon-to-be-defeated Germany, a role for France in occupied Germany, a voting formula for a new United Nations organization, and a pledge from the conferees to help all of the liberated European states "to create democratic institutions of their own choice."

But the issue that most absorbed the participants -- and that reverberates loudest to this day -- was what to do about Poland.

There is a gaunt Franklin D. Roosevelt, two months before his death, ruminating in a tired voice about how the Polish issue has been "giving the world headaches for the past five centuries."

There is a rotund and hearty Winston Churchill, whiskey glass in hand, insisting as a point of honor -- given Britain's decision to go to war against Hitler after the attack on Poland -- that Poland now be made "free and independent."

But Churchill acknowledges the Soviet interest in having a Warsaw government that would not conspire against Moscow.

And there is a shrewd Joseph Stalin, who extols the virtues of cooperation among the superpowers and chides "certain small countries" liberated by the Soviets for complaining that their interests were not being taken into account.

In one prescient exchange, Roosevelt, discussing the prospect of elections in Poland, tells Stalin with a smile that the vote must be "above suspicion, just as things were with Caesar's wife." The Soviet chief replied, also with a smile: "That's the only way Caesar's wife was spoken about, but in reality even she wasn't without sins."

Most Poles still feel embittered about what came out of Yalta. Even four decades later, westerners are often scolded by Polish friends for what is remembered here as a sellout by the United States and Britain to the Soviets. This resentment runs as a kind of countercurrent to the prowestern sentiments that dominate among the people of this communist-managed state.

Polish authorities, in contrast with the popular mood, applaud the Yalta accords as an example of superpower cooperation serving peace in Europe.

Polish publicists also have been stressing Yalta's particular value as a bulwark against German expansionism, in line with a propaganda campaign being waged by the Soviet Bloc against West Germany to coincide with the anniversary in May of the Third Reich's surrender.

Actually, the West never agreed at Yalta to Soviet control of Poland or any other part of Eastern Europe. There is no mention in the accords or accompanying notes of the establishment of communist and noncommunist spheres of influence.

On the contrary, Roosevelt and Churchill secured from Stalin a promise to hold in Poland "free and unfettered elections as soon as possible on the basis of universal suffrage and secret ballot." In turn, the western powers agreed to recognize a provisional government in Poland based on the puppet regime installed by the Soviets in 1944, which was to be broadened by the addition of Polish "democratic leaders" from inside Poland and abroad.

But as events proved, Stalin should never have been taken at his word. Soviet security forces soon began arresting and deporting members of Poland's noncommunist, anti-Nazi resistance. Elections held in January 1947 were rigged, in the view of most western observers, giving the communist-led Democratic Bloc a reported 80 percent.

The western powers had left organization of the elections up to the Soviets -- although they may have had little choice in the matter, since the Red Army did occupy the entire country.

Lists of candidates were screened in advance by the government. Two million voters were struck from the register by government-controlled electoral committees. Factory workers were directed how to vote at the risk of losing their jobs.

Also upsetting for Poles, then and now, was the manner in which their country's new borders were drawn. The eastern frontier with the Soviet Union was fixed along the so-called Curzon Line, with Roosevelt making only a half-hearted plea to an unyielding Stalin to return the treasured cultural center of Lwow to Poland. It was agreed that the Poles would be compensated with German lands for the territories lost to the Russians. But unable to settle on new western and northern borders for Poland, the Big Three postponed the issue until the Potsdam Conference five months later.

"It all happened over our heads," Jerzy Krasowski, director of the national theater, said, stating a commonly held view. "We had absolutely nothing to say."

"Most Poles would like to believe that Roosevelt and Churchill could have acted differently at Yalta," remarked Krystzna Kersten, a historical researcher at a Polish Academy of Sciences institute, doubting personally whether they really could have. "They feel those two sold out."

President Reagan has again made Yalta a subject of international political debate by telling a group of Polish Americans last August: "We reject any interpretation of the Yalta agreement that suggests American consent for the division of Europe into spheres of influence."

But while the West tends to take a negative view of Yalta, seeing in its legacy the unintended division of Europe, the communist East takes a positive view, holding Yalta up as a lesson in international cooperation.

In Poland, Yalta's 40th anniversary has brought with it a flood of articles in the official press accusing the West of trying to distort the significance of the Crimean conference. Those in the West now trying to distance themselves from the agreement are said to be undermining peace and security in Europe.

"That the Yalta and Potsdam agreements are permanent is best shown by the 40 years of peace in Europe, the longest such period in modern history of this continent, which distinguishes Europe from the rest of the world," government spokesman Jerzy Urban declared last week.

Polish officials contend that West Germany stands to gain the most if the present European order were undone. As a frequent victim of German aggression in the past, Poland is acutely sensitive to any move that might boost German power.

"If the present political map of Europe were to be annulled," said a Polish press agency commentary last week, "then Poland, obviously under a different social system, would be seriously reduced in terms of territory and would turn into a truncated state, since her western borders would not hold up."

Fearing attempts by West Germany to reclaim territory ceded to Poland after World War II, the press agency commentary added: "This is why Poles, in their best conceived national interest, should be most ardently opposed to any sort of revision of Yalta and Potsdam."

If the balance of power in Europe is ever to change, Polish political experts argue that it cannot be done in a climate of anti-Soviet propaganda generated by the West.

"The division of Europe is not the result of Yalta but of the cold war and break in cooperation between the superpowers," Janusz Symonides, director of Poland's Institute of International Affairs, said. "Who was responsible for that is another question. But Yalta for me is an example of what can be achieved when certain legitimate interests -- including the security interests of each side -- are taken into account.

"I agree that Europe should be more united," he went on, "but that is a long process, and this process, in order to take place, cannot be used by one superpower against the other."

Historian Kersten said it would make more sense for the West to remind the Soviets of the provisions of Yalta -- the call, for instance, for free elections in Poland and for democratic institutions throughout Europe -- than to renounce the agreement. "The slogan should not be: 'Do away with Yalta.' The slogan should be: 'Live up to Yalta,' " she said.

All the same, she added, there is nothing at the moment indicating the Soviets are prepared to change the balance of forces in Europe.

"What 1981 showed," she said, referring to the declaration of martial law in Poland in December of that year, crushing the independent Solidarity labor union movement, "is that the Soviets haven't the slightest intention of giving up their zone of influence. Poland will be the last place the Soviets will give it up because this is the key for them to Germany and Western Europe."

Edward Osobka-Morawski, who served in the provisional government as Poland's first postwar prime minister, is still alive and vigorous at 76. Looking back on Yalta in an interview last week, he said the decisions reached were solid ones. The problem came afterward.

"What I was unable to foresee, what I never wanted, was a one-party system," said the white-haired one-time Polish Socialist Party leader, who left government office in 1949. "I don't blame Yalta, though. It had nothing to do with it. The one-party system was a consequence of the cold war and Stalin's one-track way of thinking."