You may have heard about Nazis destroying and looting art all over Europe. But you may not know that the looting - tons of works taken from both personal and public collections - was perhaps the great pillage in history, as much a part of Nazi war planning as was military conquest.
"If you have an interest in art history, you have an interest in World War II," author Robert Edsel told CBS News' Rita Braver. "If you like extraordinary treasure hunts, it's got something for everybody. There's no way you can't be interested in this story."
This is a story that haunts Edsel.
"I like to think of it as a passion," he told Braver, "some say obsession, but there is so much of this story to be revealed."
Edsel's obsession came late. A professional-level tennis player from Dallas, he went on to make a fortune in oil and gas. By age 39, he was a multi-millionaire and ready for a change of pace. He sold his business and moved to Florence.
Before that, he had not thought much about the Nazi's impact on European art. He explained to Braver how he remembers becoming interested in the topic.
"I was walking across one of the bridges in Florence one day, the Ponte Vecchio, the one bridge that wasn't destroyed during World War II by the Nazis, and it occurred to me, almost this epiphany, that how did all these great works of art survive the destructiveness of World War II? And who were the people that saved them?"
What he learned staggered him. Not Jewish and with no relatives who had been caught up in the Holocaust, he has spent millions of dollars of his own money to write a book called "Rescuing Da Vinci" - and to co-produce a documentary titled "The Rape of Europa" to tell the story.
The Nazi war on art and the ravages of modern combat caused an unprecedented upheaval of art and cultural property that is still unraveling today.
For one thing, there was the systematic way the Nazis had gone about stealing art - how, for example, Hitler's second in command, Herman Goering, would line up items for his own collection and Hitler's, making repeated visits to the Jeu de Paume museum in Paris.
"Where he could have a glass of champagne, smoke a cigar," explained Edsel, "and make these elections of works."
"And just take them!" Braver marveled.
"And just take them!" he agreed. "And load them up on his trains, load them up on planes and send them back to Germany."
But what really cut through to Edsel was that while the Nazis were stealing and sometimes destroying treasures, the U.S. was making heroic efforts to safeguard art and architecture.
"And it's a huge change in the history of warfare," Edsel said, "to try and fight a war on the one hand and mitigate damage to cultural treasures at the same time."
And when the war was over there was another extraordinary effort: to return the art the Nazis had looted.
Arriving at Munich and Wiesbaden were the collections of Adolf Hitler, Herman Goering, and art looted from across Europe.
Under the command of General Dwight Eisenhower, a small band of American men and women, including many art historians, was assigned to find and return looted art, some two hundred works in all. They became known collectively as the "monuments men."
"I was 20 years old, just turned 20," reminisced one of them, looking at a photograph, "must have been February 1946 when this photo was taken."
Henry Ettinger, a German born American, was one of the people who found and saved the art. He still marvels at what the United States did.
"We Americans for the first time in the history of civilization, adopted a policy which said that to the victor do not belong the spoils of war."
They weren't always successful. The documentary shows how villagers hijacked a train carrying the last shipment of art that Herman Goering had tried to amass.
Hundreds of paintings and sculptures were scattered in at least six different structures.
But the monuments men had huge successes, too. They found a castle full of property stolen from the Rothchilds and other French Jews.
And they discovered Hitler's personal art hoard deep in a salt mine in the Austrian Alps.
Braver asked art historian Nancy Yeide about the importance of the "monuments men."
"Oh, they were of vital importance," Yeide told her. "Not only did they save this art and rescue it, but the records they kept in the restitutions are used by art historians today to track the provenancy of paintings in our collection."
Yeide, head of curatorial records at the National Gallery of Art in Washington, is studying how Nazis went about looting and how monument men went about tracking the rightful owners of each piece.
"Yeah, this painting was actually confiscated from a private dealer, a dealer's stock, the Seligman Gallery in Paris," Yeide explained, showing Braver one work, "and then taken by Goering and kept in his personal collection throughout the war. And it was recovered by the monuments men with the rest of Goering's collection in Berchtesgaden."
Later the family sold the piece, which is how it ended up here. Other works which the Nazis has seized in Austria were returned by the monuments men and were later sold by their legitimate owners.
"There's such an irony there," Braver observed. "You have people who are in the middle of committing genocide and yet, here they are, fancying themselves connoisseurs of art?"
"Yes, it is, actually, very ironic, Yeide agreed. "The very people they were eradicating, they were taking their art and keeping track of whom they take the art from."
Uncovering the story of how Americans helped return some of that art earned Robert Edsel the 2007 National Humanities Award and last spring, resolutions were passed in both houses of Congress to recognize the work of the monuments men.
"They were overlooked after the war," Edsel said, "but these Congress people and senators fully embraced the story as I went around and told them."
Four of the 12 living monuments men, including Harry Ettinger, were there in Washington that day to reminisce about a time and place where good really did triumph over evil.