VITERBO, Italy (AP) _ After decades behind the Iron Curtain, hundreds of Etruscan artifacts have returned to Italy in a major show from museums in Eastern Europe and the Soviet Union.

The 1,200 artifacts, which were nearly inaccessible to Westerners for decades, have come home to central Italy, where the Etruscan culture flourished until the 1st century B.C.

The exhibit is being hailed as a chance for scholars and the public to rediscover Etruscan masterpieces hidden away for decades.

It also is seen as a sign of exciting times to come in the art world, as the new democracies of Eastern Europe begin to exchange exhibits with countries that were ideological foes.

''This brings together an extraordinary number of masterpieces that were very little known,'' said Massimo Pallottino, president of the National Institute of Italian Etruscan Studies.

''It's something of exceptional importance.''

The exhibit in a Gothic castle in Viterbo, 50 miles north of Rome, was organized by the State Museums of Berlin.

It includes Etruscan artifacts from 26 museums in Poland, Hungary, Czechoslovakia and the former East Germany, as well as the Soviet Union.

The Etruscans were a powerful empire that dominated Italy before succumbing to the Roman Empire. They were known for commercial flair, an elaborate religion and a brilliant artisan tradition, which included the finest goldwork in ancient Europe.

The Viterbo show brings together a wide range of Etruscan artifacts, ranging from a simple ceramic urn shaped like a house dating from the 9th century B.C., to elaborately carved sarcophagi from the 2nd and 3rd centuries B.C.

The highlights include the contents of an 8th century B.C. tomb of a man known as the Warrior of Tarquinia. Among the 104 pieces are engraved bronze shields, weapons, bracelets, rings and even a razor for the afterlife.

Another rare item is the ''Tile of Capua,'' a 5th-century B.C. plaque with writing believed to be part of a funeral ritual. It is the second-longest existing piece of Etruscan writing, which scientists have never succeeded in translating.

Several carved stone and alabaster sarcophagi with scenes of battles or the trip to the afterlife illustrate the Etruscans' talent for sculpture. On top of a few lies a likeness of the dead person, often propped up on one elbow as if to enjoy a good Etruscan meal.

Also in the exhibit is gold jewelry, including tiny earrings etched to resemble shields or bunches of grapes from the 3rd to 5th centuries B.C.

Many Etruscan treasures wound up in German and Russian hands in the 19th century, before Italy passed a law limiting exports. Germans, in particular, did much of the early research on the Etruscans and were interested in acquiring the pieces.

Many of the items in the exhibit were difficult for Westerners to see during Communist rule in Eastern Europe, due to the difficulty of obtaining tourist visas.

''Even some of our experts hadn't seen them,'' said Carlo Maria Cardoni, director of the exhibit.

For the Italian organizers, the novelty of having treasures from Eastern European museums was matched by the novelty of working with museum officials trained under communism.

''Their architect still goes around with a wooden ruler and a pencil,'' said Cardoni, shaking his head. ''Let him see a computer that in 35 minutes lays out the show, and it's like hitting him in the head with a hammer.''

The Germans were also uneasy about the idea of making a videocassette of the exhibit, Cardoni said. ''I just went ahead with it anyway,'' he shrugged.

The show, which closes Sunday, has toured Eastern Europe and the Soviet Union and may eventually go to France or Japan, Cardoni said.

Art experts say the show is an example of the revolution that is occurring in cultural exchanges now that Communist governments have fallen or become more moderate.

''As curators and scholars, there's always been an international interest in sharing the cultural wealth of one nation with another,'' said Jillian Slonim, public information director of the New York-based American Federation of Arts.

''On the practical level, the circumstances have radically changed in the last short while, along with the changes in the governments.''