WASHINGTON (AP) — When art historians saw Paris fall to the Nazis in World War II, they immediately realized Europe’s vast monuments, art, cathedrals and architecture were at risk and began mobilizing to protect such treasures.

In Washington, the newly opened National Gallery of Art became the U.S. museum world’s epicenter for lobbying President Franklin D. Roosevelt and the Allied forces in 1941 to prevent the destruction of Europe’s monuments. Their efforts would create a corps of U.S. and British soldiers who worked to protect cultural sites and recover looted art after the war.