Theodor Eicke
Zeireis replaced Albert Sauer as commandant of Mauthausen on 9 February 1939 by order of Theodor Eicke, Inspector of Concentration Camps. On 25 August 1939, Ziereis received a promotion to the rank of SS-Sturmbannführer and, on 20 April 1944 he received his final promotion to SS-Standartenführer.