From the fall of 1943 to the spring of 1945, the Castle at Nikolsburg was transformed into a depot of works of art and objets d’art stolen by the Einsatzstab Reichsleiter Rosenberg (ERR) mostly in France, and to a lesser extent in Belgium, and Holland. At least 5 trains filled with loot packed into hundreds of crates made their way from Paris to Nikolsburg where they were dutifully unloaded and placed in dozens of rooms throughout the Castle. As the Western Allies advanced across France, Belgium and Holland, many of the crates were transferred to Altaussee in the Salzkammergut section of Austria where the Reich authorities had created a central underground facility consisting of a network of salt mine galleries in which to store plundered art from across Europe. Not all the crates from Nikolsburg, however, made it to Altaussee. An unknown number remained at the Castle.
In the final days of the Second World War, a fierce battle raged in and around Nikolsburg opposing retreating German forces and advancing Red Army units. The town was not spared and the Castle took massive artillery hits. As Soviet troops closed in on the town, the occupants of the Castle removed many of the remaining objects to safer locations across town, including the local museum. A major fire produced by systematic shelling gutted the Castle. To this day, it is not clear how much of it burned down.
French restitution authorities including Rose Valland concluded that the Castle had burned to a crisp and its contents turned to ash. Curiously enough, however, two years after this hasty verdict was pronounced, the Czech government returned to France several hundred items from Nikolsburg/Mikulov which bore the identifying numbers assigned to them by the ERR in occupied Paris, at the Jeu de Paume, where they had been brought and sorted.
Some of these items belonged to Veil Picard (WP), David David-Weill (DW), Louis Louis-Dreyfus (DRF, DRD), the Hirsch family (HIR), the Oppenheimers (OPPE) and many others, including objects seized during Möbel-Aktion (MA-B).
Until a full accounting is produced of the items stored at Nikolsburg, a doubt will always linger whether more objects from the Nikolsburg hoard remain in the Czech Republic or in Slovakia or even perhaps in Austria. No one knows for sure.