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The Nazi rank achieved by Ernst Kaltenbrunner was SS-Oberst-Gruppenführer, the second highest rank in the SS, equivalent to General of the Police in the regular police. He rose through the ranks rapidly during World War II, becoming the Chief of the Reich Security Main Office (RSHA) in 1943, overseeing the Gestapo, Kripo, and SD, making him one of the most powerful figures in Nazi Germany.