Josef Kramer was a Hauptsturmführer and the Commandant of Auschwitz-Birkenau and of the Bergen-Belsen concentration camp. Dubbed The Beast of Belsen by camp inmates, he was a German Nazi war criminal, directly responsible for the deaths of thousands of people. He was detained by the British Army after the Second World War, convicted of war crimes, and hanged on the gallows in the prison at Hamelin by British executioner Albert Pierrepoint.

Hauptsturmführer was a Nazi Party paramilitary rank that was used in several Nazi organizations such as the SS, NSKK and the NSFK. The rank of Hauptsturmführer was a mid-level commander and had equivalent seniority to a captain (Hauptmann) in the German Army and also the equivalency of captain in foreign armies.