BERLIN (AP).- A painting of the Florence skyline that hung in Adolf Hitler's Berlin apartment throughout World War II and was missing for decades went on show Thursday in an exhibition of works returned to the collection of a major German museum.
The exhibition centers on 18 works returned to the Alte Nationalgalerie over the past decade, more than half a century since they were removed from its premises.
It also uses official shipment and loan lists, photographs and other documents to show how these pieces were taken down from the museum walls to wind up on odysseys through flak towers, salt mines and water-soaked cellars.
Many of these works found their way into private hands, but museum officials say a recent international push for restitution has resulted in an increase in the number of works returning to the museum in the past 10 years.
"In recent years, attitudes have changed," said Dorothea Kathmann, a legal expert with for the Prussian Culture Foundation. Efforts to track down and restitute art looted from Jewish collectors by the Nazis have helped encourage a broader focus on tracing pieces that were stolen or went missing during the Nazi era and World War II.
"Today not only the question of ownership is in focus, but attempts to trace Jewish collections, have brought an ethical and moral even political element" to research, Kathmann said.
At the end of the World War II in 1945, some 800 works that had been in the collection of the Alte Nationalgalerie were missing. About two-thirds of them were recovered by the end of the 1950s. Since 1990, more than two dozen others have been returned, including those in the exhibit.
Political developments, including Germany's and Berlin's reunification and use of the Internet to circulate databases, however, have made it easier to spread the word about missing artworks, leading to a jump in the number of returns since 2000, Berlin Museum director Michael Eissenhauer said.
"A View of Florence," by 19th-century German painter Wilhelm Ahlborns, was one of 68 works loaned by the gallery to the Nazi regime and hung in Hitler's private quarters at his chancellery. Earlier this year, it turned up in a Berlin art gallery, which in turn alerted the museum.
Kathmann said that in most cases, once the gallery proves ownership, using pre-war documentation or markings on the paintings themselves, it has been able to negotiate a "finder's fee" for the current owners, worth roughly 10 percent of the picture's market value.
"From our point of view, we do not see a need to pay for the works a second time," Kathmann said.
Another work in the exhibit, which opens to the public on Friday and runs through March 6, was reacquired by the museum in October.
In 1942, "Dog with Gray Horse" by English painter William Cole, had been hung by Nazi officials in a Berlin villa that was to house the then exiled Iraqi prime minister. At the war's end, he moved south to a village outside Dresden and the painting was given to a housekeeper as payment.
A descendent of the housekeeper identified it through a database of lost artwork and contacted the museum reflecting what Eissenhauer called a generation change that is benefiting the museum.
"Many paintings are changing hands and the younger generation is starting to ask where they come from," Eissenhauer said. "We are hoping that the curve will continue to go up."
Copyright 2010 The Associated Press.