The Holocaust was the attempted destruction of European Jewry by Nazi Germany. Six million Jews and five million non-Jews were murdered. Test your knowledge of one of the darkest times in history.

Photo: Boys on a curb in the Warsaw ghetto. Photographer Joest's original caption reads: "It was striking to me how many youngsters did not wear shoes. It was already cold on this day." September 19, 1941, Warsaw, Nazi-occupied Poland.

Photo credit: United States Holocaust Memorial Museum, courtesy of Guenther Schwarberg.