WASHINGTON, Nov. 5 (JTA) – When thousands of art enthusiasts viewed an exhibit of impressionist paintings at the National Gallery of Art here in 1990, little did they know Nazi plunder was hanging on the walls. The museum made no mention of that fact at the time. It also did not reveal the collector’s background. Now, seven years later, B’nai B’rith is demanding an explanation for the way the museum handled the exhibit, “The Passionate Eye: Impressionist and Other Master Paintings From the Collection of Emil G. Buhrle.” “The exhibit raises a myriad of questions, including why the prestigious National Gallery of Art gave a public platform to a Nazi arms dealer who was also the largest Swiss buyer of looted art,” said Sidney Clearfield, executive vice president of B’nai B’rith. Questions about the exhibit – and the museum’s failure to fully disclose Buhrle’s background – come as inquiries into the whereabouts of Nazi-looted artwork have intensified in recent months. During their march across Europe, the Nazis confiscated artworks from prominent Jewish collectors and dealers. Ordinary people also lost their art treasures when they were forced to flee their homes or were deported to death camps. The National Gallery of Art “is concerned that questions have been raised about works of art that were shown for nine weeks in a temporary loan exhibition seven years ago in 1990,” the museum said in a statement. “The gallery makes all reasonable efforts to assure itself that it exhibits works of art that have been properly exported from their country of origin and that have no legal claims regarding ownership pending against them. We are constantly seeking to improve our procedures.” A spokeswoman for the museum refused to elaborate or answer questions about why the museum omitted information about the collection. B’nai B’rith said it was particularly outraged by the National Gallery’s omission of facts about Buhrle’s collection because it said information on Buhrle’s past and his art was available to the public as early as the 1970s. “I would find it enormously difficult to believe that it was an oversight, that their researchers and curators could have been so incredibly sloppy,” said Ori Soltes, director of the B’nai B’rith Klutznick National Jewish Museum. Most of the major pieces in Buhrle’s collection originally belonged to Paul Rosenberg, a prominent Parisian art dealer who lost much of his collection to the Nazis. Soltes said that after the war Rosenberg successfully reclaimed his art from Buhrle through a court order, but then sold many of the works back to Buhrle. Although Buhrle was, in fact, the rightful owner of the collection displayed at the National Gallery, Soltes said the catalog on the exhibition made no mention of the artworks’ previous owners or history. He said it also referred to Buhrle as an anti-Nazi crusader – not as a Nazi arms dealer. “For a major institution to gloss over all of that strikes me at the very least as intellectually strange and pedagogically inappropriate,” Soltes said. B’nai B’rith has called on the museum to correct the catalog, which it said is now sitting in libraries and universities around the world as the historical document of record about the lineage of paintings in the exhibit. The National Gallery said that because it did not publish the catalog, it cannot reprint it. B’nai B’rith said it was also working with the American Association of Museums to develop guidelines pertaining to the acquisition and display of plundered art. The Klutznick Museum, meanwhile, is sponsoring a Holocaust Art Restitution Project to establish a database on art losses and to research and document Jewish cultural losses. The 1990 exhibit, which included works by Degas, Matisse and Cezanne, was organized by the Buhrle foundation in Zurich and by the National Gallery in commemoration of the 100th anniversary of Buhrle’s birth. It contained mostly impressionist and post-impressionist works, and traveled to Canada, Japan and England after it left Washington, D.C.