BERLIN (Reuters) - The heirs of Jewish art dealers who say their families were forced to sell the Nazis a trove of medieval church treasure worth some $250 million today have turned to a U.S. court to reclaim it, after failing in their attempts in Germany.
The collection, known as the Guelph Treasure, consists of 44 gold, jewel and pearl encrusted pieces which have belonged to the city of Berlin's art collection since their purchase in 1935, on the orders of leading Nazi Hermann Goering.
Germany says an expert committee established last year that the sale was not forced, following a 2008 claim by the heirs.
The reliquiaries dating from the 11th to 15th centuries were once owned by northern German aristocrats and kept in Brunswick cathedral. Today they are on show in Berlin's Bode Museum.
Lawyers for the heirs of the dealers, who bought the collection from the Duke of Brunswick in 1929, said on Tuesday they filed a civil suit with a district court in Washington DC, appealing to the U.S. Foreign Sovereign Immunities Act (FSIA).
They say the court has jurisdiction because the FSIA covers violations of international law, such as forced property sales.
A Jewish refugee from Austria, Maria Altmann, used this law in 2000 to recover paintings by Gustav Klimt. She successfully fought the case all the way to the U.S. Supreme Court and was then awarded ownership by an Austrian court of arbitration.
"The fingerprints of Goering and Hitler are on this sale, the dealers had no chance," restitution lawyer Markus Stoetzel said.
The Jewish dealers sold the works to the state of Prussia for 35 percent of its value, lawyer Nicholas O'Donnell said.
Ingolf Kern, a spokesman for the Prussian Cultural Heritage Foundation, said he was surprised by the move, given that the advisory commission had found the price was reasonable.
The consortium of dealers bought 82 pieces in 1929 for 7.5 million Reich marks and then sold 40 for 2.5 million marks. The Prussian state paid 4.25 million marks for the rest in 1934-35.
The commission said the market was depressed in the early 1930s, Prussia was the only interested buyer and the works were stored in Amsterdam at the time, although the dealers were based in Germany.
This month Berlin designated the Guelph Treasure of national cultural value, making it impossible for it to leave the country without the approval of the culture ministry.
"If they were so sure they owned it, they wouldn't need to do this," said O'Donnell.
Kern argued, however, that this was a logical move for Germany's most precious artifacts.
Germany has faced criticism for its handling of artworks looted by the Nazis, with some museums accused of reluctance to research the provenance of suspect works.
Reporting by Alexandra Hudson; Editing by Stephen Brown and Angus MacSwan