Since at least the 19th century, there has been an undercurrent of illegal activity running through the market for Greco-Roman antiquities. Due to the fact that it was the Europeans and Americans who first made archaeology an accepted pursuit, and many wealthy Europeans and Americans who pursued the collection of ancient treasures while the Greeks and Italians were still busy scratching out an existence, many of the foremost pieces remaining from the ancient world reside in museums outside their areas of origin. For example, the magnificent Altar of Zeus from Pergamum is in the Berlin Pergamon Museum, and the equally inspiring Elgin Marbles are to be found in the British Museum.
Although at least some of these treasures were acquired legitimately (in the case of the Elgin Marbles, Lord Elgin paid the Greek government of the time for their removal) there has been ongoing controvery over who actually should have possession. Throughout much of the 20th century, Greece and Italy have conducted campaigns for the return of these treasures. And modern-day museums and collectors pay millions for pieces from sometimes less-than-pure sources.
Today, we are reminded of this undercurrent by the announcement here that the Getty Museum has agreed to return to Italy three works that are the subject of a criminal trial. These were part of a larger consignment that Italy and the Getty Museum have yet to agree on. In fact, Italy is trying the Getty's antiquities curator on charges of rconspiring to receive stolen property. I guess every field has its own share of illicit activity- particularly when dealing in art and sculpture.