HALLE, East Germany (AP) _ After years of championing better East-West relations, Foreign Minister Hans-Dietrich Genscher of West Germany returned to his East German hometown to be hailed as the architect of unification.

The whirlwind events of the last few months have bolstered Genscher, one of the first to take Mikhail S. Gorbachev at his word when the Soviet leader promised reform.

Even occasional backbiting by U.S. and British officials failed to stop Genscher, an affable and unflappable veteran diplomat whose protruding ''elephant ears'' have become his trademark.

Referring to Genscher's legendary globe-trotting, Soviet Foreign Minister Eduard Shevardnadze once joked that whenever two airliners cross paths over the Atlantic, ''Genscher is on both of them.''

While German unification itself would be his crowning achievement, Genscher's trip back home Friday to the decaying industrial city of Halle provided an emotional high point.

About 60,000 people crammed into the marketplace to give him a rousing hero's welcome, handing the 62-year-old diplomat flowers and chanting for him to stay with them.

While the outdoor event was a campaign rally for the East German counterpart of Genscher's Free Democrats, there was no doubt about the real star of the show.

A large banner on the town hall steps read ''Halle Welcomes Hans-Dietrich Genscher, Architect of Unity.''

The local newspaper featured a spread about Genscher's childhood in the city he left behind when he fled his Communist homeland for West Germany nearly 40 years ago.

''Genscher was the man who made all these developments toward German unity possible,'' said Albrecht Klemenz, a 37-year-old physicist in Halle. ''He worked for years to win trust and improve relations between the two blocs, and that was an important precondition.''

For several years, officials in Washington and London used the term ''Genscherism'' to describe what they saw as an attitude of excessive confidence in Moscow.

Now, Germans invoke the same term proudly to sum up their country's achievements as a visionary force in European diplomacy.

Perhaps Genscher's first major victory came in September. After weeks of frantic efforts, he appeared on the balcony of the West German Embassy in Prague, Czechoslovakia, and told thousands of East Germans they could leave for West Germany.

The roar of approval touched the usually calm politician, who has served as foreign minister since 1974.

''That was the most moving point of my political career,'' Genscher told reporters outside the embassy compound.

In his speech Friday, Genscher called for immediate recognition of Poland's present borders. This would ease Polish worries about losing to a united Germany land it gained from Germany after World War II, and it would remove an obstacle to reunification.

''Both German states can make an important contribution to stability in Europe after the March 18 (East German) election by saying, 'We Germans do not have territorial claims on any one of our neighbors, also not on the Polish people,''' he told the cheering crowd. Many spectators carried West German flags.

''This peaceful revolution in East Germany has brought honor to our entire German nation. I am proud of Halle on the Salle 3/8'' he said, visibly moved. Halle lies on the Salle river in Saxony in the southwestern part of East Germany.

At the end of the speech, the crowd mobbed Genscher, shouting ''Hans- Dietrich 3/8'' along with the now-familiar ''Germany United Fatherland 3/8''

Genscher was born in the nearby suburb of Reideburg, and his parents later moved to Halle itself. He returned to the Soviet-occupied sector of his homeland after he was captured by the Americans and imprisoned in Britain until the end of World War II.

The local newspaper Freiheit mentions a cousin in the suburb of Liskau as possibly the only immediate Genscher relative left in the area.

Freiheit featured an interview with that cousin, Werner Ruehl, in its Friday edition.

''We haven't lost contact since 1952,'' the newspaper quoted Ruehl as saying, referring to the year Genscher escaped to the West after growing disenchanted with the Communist state. ''He visits us every year, usually around Christmas.''

Genscher has long been troubled by health problems, including heart trouble and a bout of tuberculosis in the 1950s.