The character of Claire Simone, played by Cate Blanchett appears to have been based on Rose Valland, a Parisian museum curator who was drafted by the Nazis during the occupation of Paris to assist with art acquisitions. As depicted in this film and in the documentary The Rape of Europa (2006), Valland secretly kept a detailed ledger of all works that passed through Nazi hands, the original (often Jewish) owner of each work, and the location in Germany where each item was eventually transported.
The map of Germany and the Low Countries that Stokes and his men look at shows a map with modern day coastlines, including the Dutch province of Flevoland. However, the 1,000 square kilometer insular province only came into being when it was reclaimed from the sea in 1968, well after the Second World War. Also, the "Afsluitdijk" (a 32km long dam sealing off the Zuiderzee) is not shown on the map, despite having been completed in 1933.
The Madonna was mentioned several times as having been stolen from the cathedral in Bruges. In reality, the Madonna is on display in the Church of Our Lady, not the cathedral of St. Saviours.
When Sgt. Garfield and Lt. Clermont are shot at by a Nazi Youth, Sgt. Garfield lays down covering fire from his M1 Carbine, but fires over 20 rounds without reloading from a 15 round magazine.