The debt the world owes the Monuments Men—approximately 350 servicemen and women from 13 countries who worked in the Allied Monuments, Fine Arts, and Archives program during World War II—has recently become better known thanks to an excellent documentary based on a phenomenal book, plus a highly fictionalized version of the story brought to the big screen by George Clooney. Their dedication in tracking down and repatriating millions of great works from Europe's museums and private collections that had been stolen by the Nazis ensured that many treasures of Western art found their way home at the end of the war, instead of rotting in salt mines and warehouses.

Less well-known is the work done before the war to keep one of the greatest collections of art and artifacts in the world—the Louvre Museum's in Paris—out of Nazi hands in the first place. Hitler and his cronies had a wish list of works they planned to plunder from the countries they invaded, and Leonardo da Vinci's Mona Lisa, the most famous painting in the world then and now, was at the top of the list. It was Jacques Jaujard, director of France's National Museums, who thwarted Hitler's scheme, pulled the wool over the eyes of the collaborationist tools of the Vichy government, and kept the Louvre's contents, including the Mona Lisa, safe for the duration of the war.

After Germany annexed Austria in March of 1938, Jaujard, then deputy director of the National Museums, lost whatever small hope he had that war might be avoided. He knew Britain's policy of appeasement wasn't going to keep the Nazi wolf from the door, and an invasion of France was sure to bring destruction of cultural treasures via bombings, looting, and wholesale theft. So, together with the Louvre's curator of paintings René Huyghe, Jaujard crafted a secret plan to evacuate almost all of the Louvre's art, which included 3600 paintings alone.

Aside from modestly sized works like the Mona Lisa, the pieces they were rescuing included delicate artifacts such as the 4000-year-old Seated Scribe, monumental paintings such as Théodore Géricault's 16-by-24-foot The Raft of the Medusa, and massive statues such as the Winged Victory of Samothracewhich weighs 3 metric tons.

© Rijin S via Wikimedia Commons // CC BY-SA 4.0

 
On August 25, 1939, Germany and the Soviet Union announced their Nonaggression Pact and Jaujard made his move. That day, he closed the Louvre for three days (ostensibly "for repairs") and his meticulous plan went into action. The Louvre staff, students from the École du Louvre, and workers from the Grands Magasins du Louvre department store took paintings out of their frames (when possible) and moved statues and other objects from their displays into wooden crates. All works were labeled with marks indicating their evacuation priority—yellow dots for most of the collection, green dots for the works of major significance, and red dots for the greatest treasures of global patrimony. The Mona Lisa was placed in a custom poplar case cushioned with red velvet. The box was crated up and the crate marked with three red dots, the only work in the entire collection with that rating.

On August 28, 1939, hundreds of trucks organized into convoys carried 1000 crates of ancient artifacts and 268 crates of paintings and more to the Loire Valley, where the splendid châteaux had room to host the art far from likely bombing targets. In just three days, 200 people packed 3600 paintings—plus many more drawings, sculptures, objets d'art, and antiquities—into crates. Giant paintings like The Raft of the Medusa that were too fragile to be removed from their frames and rolled up had to be transported vertically, for which Jaujard secured scenery trailers from the Comédie-Française. The Mona Lisa was transported in an ambulance, on a stretcher with elastic suspension to keep it as safe as possible from jostling.

To keep the Mona Lisa safe from interception, Jaujard made sure there was no indication on the crate of its contents. He gave the painting a code instead, writing the letters "MN" in black, without the department letters or the red number that was the standard packing notation on other crates. Later, he wrote to the curator newly in charge of the piece to let him know which crate the masterpiece was in, and to add "L.P.0" in red to the code on the crate ("LP" stood for "Louvre Paintings"). The Mona Lisa arrived safely at the Château de Chambord, the largest château in the Loire Valley, along with the rest of the Louvre's collection. There, the works would be triaged and split up for transport to other rural châteaux, museums, and abbeys.

 
Four days later, on September 1, 1939, Germany invaded Poland. On September 3, France declared war on Germany, triggering the evacuation of the final work: the Winged Victory of Samothrace, which by the grace of some higher power and the dedication of the Louvre curators and staff, made it down the steps and into a truck to safety.

In November of 1939, the Mona Lisa was transported from Chambord to the château of Louvigny, the northernmost art depot where the large-format paintings were stored, to keep it out of reach of the advancing German army. The crate was on an ambulance stretcher again, this time in an armored van that was sealed shut to keep the humidity constant. A curator sat next to it in a state of cat-like readiness for the entire trip, and later reported the lack of air circulation almost suffocated him.

Safety was a tenuous concept in wartime France. Jaujard and other officials would juggle logistics and arrange additional moves at great personal risk for the duration of the war to keep France's cultural treasures out of Nazi hands, out of Vichy hands and, working directly with the French Resistance, out of range of Allied bombs. The Mona Lisa would be moved five more times to stay ahead of the maelstrom.

In June of 1940, with the surrender of France imminent and floods of refugees from Belgium, Holland, and northern France clogging the roads south, many of the Louvre's works were moved out of the German-occupied north into what would soon become the southern "free zone" of the puppet Vichy government. The Mona Lisa was sent to the former Cistercian Abbey of Loc-Dieu. It had burned down in 1409 during the Hundred Years' War, and when it was rebuilt in 1470, it was fortified against any such future eventualities.

A fortified abbey in the south of France seemed like a solid choice to protect the Mona Lisa and other masterpieces, but within months, conservators became concerned that the humid environment would damage the paintings. Mona Lisa and friends were moved again, this time even further south to the Musée Ingres in Montauban, 35 miles north of Toulouse. There the Mona Lisa arrived on October 3, 1940, and stayed for just over two years in the former residence of the bishops of Montauban. Calamity almost struck twice: once in December of 1941, when a ceiling beam came loose in the room where the Louvre's works were being stored, and once in August of 1942, when a violent thunderstorm caused massive flooding that penetrated the museum and dampened 69 paintings. The Mona Lisa was not one of them.

But by early 1943, Jaujard feared that the Musée Ingres was no longer safe. Germany had invaded the free zone in November of 1942, and the museum was close to a bridge over the Tarn River that Jaujard knew might make an attractive bombing target. In February 1943, the Mona Lisa was moved again to its final wartime hiding space, the Château de Montal in southwestern France.

Paris was liberated by the Allies on August 25, 1944. On May 8, 1945, Germany unconditionally surrendered and the war in Europe was over. Finally, the Louvre's works began to come back home. The museum had seen some rough treatment during the war: The Germans had kept it open, its galleries mainly empty except for some lesser pieces fished out of storage and boxes of looted artworks from Jewish private collections that were stashed in the museum before transport to Germany. The Louvre was extensively renovated between 1945 and 1946, its galleries opened piecemeal as they were completed. The Mona Lisa returned on June 16, 1945.

Mona Lisa rehung at the Louvre October 6, 1947, reopening. Image credit: AFP/Getty Images.

 
Or did it? Between the chaos of war and Jaujard's probable use of period copies of the Mona Lisa as decoys, there are conflicting reports about where exactly she went and how she made it back. One Austrian museum near the Altaussee salt mine claimed that "the Mona Lisa from Paris" was among "80 wagons of art and cultural objects from across Europe" the Nazis stored in the mine. But the one that returned to the Louvre is far more likely to be real thing, and the one in Altaussee a high-quality copy. Many people worked very hard for six years to keep the painting in France, and today there's little doubt that the Mona Lisa hanging in the Louvre, encased by bullet-proof glass, is the one painted by Leonardo da Vinci 500 years ago.