It was true that the painting had been sold in 1909 at a Berlin auction. There is, however, no record of the name of the buyer at that date. In 1962, Mr and Mrs Dickson Hartwell, the then owners, offered the Cranach to the Metropolitan Museum in New York, which turned it down, after which the National Gallery bought it from the Silbermanns. At that time, there was not a great deal of interest in the question of art and the Holocaust.
Things were very different in 1998 when Mrs Hartwell died, and they remain so to this day. In a series of high-profile cases, where works of art have been shown to have been confiscated by the Nazis, or sold under pressure, or handed over as bribes to secure escape from Germany, restitution has been made. Sometimes a gallery has paid the full price for a painting on its wall, as Berlin did for a Caspar David Friedrich. Sometimes major works have left the cities in which they became famous, as the Klimts recently left Vienna to be sold in New York. A painting by Adolph von Menzel was acquired in this way not long ago by the National Gallery in London (on whose board I serve), having hung previously in Dresden.
When a case for restitution is successfully made, the museum or gallery in question faces a familiar choice: either to negotiate a purchase from the heirs or to let the work go. The only thing to regret about this situation is that it has taken so long to bring it about. The connection with the original owners is becoming ever more tenuous.
In 1998-99, the National Gallery drew up a list of paintings in its collection with incomplete provenances, including the Cranach in question. Five years later, Mrs Hartwell's son, Jay Hartwell, contacted the gallery with the extraordinary story of his mother's acquisition of the painting. Patricia Lochridge Hartwell had been a war correspondent for Collier's Weekly and the Women's Home Companion. She saw the liberation of Dachau in 1945. It must have been soon after this that she was offered by the American forces one of the paintings they had found in various Nazi caches. She chose the Cranach and was able to take it home with her to the States.
When this story was published in 2006, it was guessed that the painting could have come from Hermann Goering's collection. But all the Nazi leaders seem to have had a passion for Cranach. It was part of nationalist ideology: "In the shadow of their sword, Dürer, Holbein and Cranach created their works of art for the German people. Are they not brothers, the artists and the soldiers?"
The name of Cranach runs as a leitmotif through the study by Lynn H Nicholas of Nazi looting of art, The Rape of Europa (1994). If he was Goering's favourite artist, he was also high on Hitler's list. When Hitler visited the Uffizi with Mussolini, their guide tried to hurry him round in case he asked for their great Cranachs. ("Tutti questi quadri ..." Mussolini muttered: All these pictures ...) The great collector Robert von Hirsch bought exit from Germany for himself and his collection with a Cranach. Georges Braque, though an Aryan and supposedly immune to confiscation, was obliged to sell a Cranach in order to secure the safety of his collection. What had been worth an exit visa under the Third Reich became, with the liberation, equivalent to a pair of nylons.
There are large numbers of paintings by Cranach and his studio - more than a thousand have survived - and many of these are replicas and variants on themes. So it is by no means straightforward to identify and trace the fortunes of all Cranachs during the Nazi period. The art historian Birgit Schwarz, author of a study of Hitler's collection for his museum in Linz, discovered in Washington a photograph album that apparently records the paintings in Hitler's private Munich apartment. Among these is what appears to be the National Gallery's painting.
There is also a list, apparently drawn up by the photographer Heinrich Hoffmann, who, though no art expert, helped Hitler with his collecting. This includes a Cranach, but it is described as "Eve plucking the apple of Paradise" - Hoffmann misunderstood or misremembered the subject, which has Venus under the apple tree while Cupid, holding the honeycomb, complains at being stung by the bees.
It is Schwarz who, having discovered the Washington photo album, first asserted that Hitler had this Cranach in his apartment. There seems to be a minor inconsistency in her story. If this is the Cranach referred to by Ward Price as "recently acquired" in his 1937 book, it could not also be the "nude Venus" given by Fritz Sauckel, the Reich Regent of Thuringia, to Hitler for his 50th birthday in 1939. Clearly, Hitler had more than one Cranach.
Nothing that Schwarz has yet found casts any light on the identity of the previous owner of the National Gallery picture. The assumption is strong that the source was Jewish, but the key piece of this particular jigsaw is still missing.