Polish Deputy Culture Minister and Head of Conservation Piotr Zuchowski speaks at a news conference Friday in Warsaw, Poland, on the so-called Nazi gold train. Radek Pietruszka/EPA/Landov hide caption

itoggle caption Radek Pietruszka/EPA/Landov

French far-right National Front founder Jean-Marie Le Pen arrives for a news briefing at party headquarters in Nanterre, near Paris, on Thursday. The executive committee decided to expel Le Pen from the party over remarks downplaying the Holocaust. Christian Hartmann/Reuters/Landov hide caption

itoggle caption Christian Hartmann/Reuters/Landov

The new Russian Armata T-14 tank shown during the Victory Day military parade in the Red Square in Moscow, on Saturday. Yuri Kochetkov/EPA/Landov hide caption

itoggle caption Yuri Kochetkov/EPA/Landov

Cartoonist Art Spiegelman attends the French Institute Alliance Francaise's "After Charlie: What's Next for Art, Satire and Censorship" at Florence Gould Hall on Feb. 19 in New York City. Mark Sagliocco/Getty Images hide caption

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Former SS guard Oskar Groening, now 93, enters a car after the first day of his trial in Lueneburg, Germany, on Tuesday. He faces 300,000 counts of accessory to murder, in a case that tests the argument that anyone who served at a Nazi death camp was complicit in what happened there. Markus Schreiber/AP hide caption

itoggle caption Markus Schreiber/AP

The Nazi concentration camp Auschwitz I in Poland, circa 1945. Writing over the gate reads "Arbeit macht frei" (Work Sets You Free). Johann Breyer has admitted to working as a guard at the camp but says he only supervised work parties outside the gates. Uncredited/AP hide caption

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The names of Jeffrey Katz's family members are depicted on "stumbling stones" in Lembeck, Germany. His relatives owned a home on the property near the stones, before they were evicted in 1942. Jeffrey Katz/NPR hide caption

itoggle caption Jeffrey Katz/NPR