Martin Sommer
Walter Gerhard Martin Sommer (8 February 1915 – 7 June 1988) was a German SS Hauptscharführer (master sergeant) who served as a guard at the concentration camps of Dachau and Buchenwald. Sommer, known as the "Hangman of Buchenwald", was considered a depraved sadist who reportedly ordered two Austrian priests, Otto Neururer and Matthias Spanlang, to be crucified upside-down.
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