Bergen-Belsen, or Belsen, was a Nazi concentration camp in what is today Lower Saxony in northern Germany, southwest of the town of Bergen near Celle. Originally established as a prisoner of war camp, in 1943, parts of it became a concentration camp. Initially this was an "exchange camp", where Jewish hostages were held with the intention of exchanging them for German prisoners of war held overseas. The camp was later expanded to hold Jews from other concentration camps.

From 1933 to 1945, Nazi Germany operated more than a thousand concentration camps, including subcamps on its own territory and in parts of German-occupied Europe.