After the armistice, his ship along with the rest of the German High Seas Fleet was interned by the British at Scapa Flow.

After the German Sailors scuttled their ships, they were held in English prisoner of war camps.

[2] From 1936, Mazuw was a member of the Reichstag of the Nazi Party from the tenth to the eleventh electoral period for the 6th constituency, Pommern.

From April 1936 until the beginning of May 1945, Mazuw was leader of the Ostsee SS-Oberabschnitt, and from August 1938 to the end of the same period, he was Higher SS and Police leader (HSSPF) in the district Nord ("North"), in 1940 renamed Ostsee ("Baltic Sea"), with his office in Stettin.

[3] In this position, together with Pomeranian Gauleiter Franz Schwede-Coburg, he was engaged in the "Aktion T4" euthanasia action, aiding the dispatchment of some 1,400 mental care clients from Pomeranian sanatories in Stralsund, Ueckermünde, Treptow an der Rega, Lauenburg and Meseritz-Obrawalde to an execution site in Piasnitz, Reichsgau Danzig-West Prussia, where they were shot.

[6] Writer Igor Witkowski has speculated that Mazuw was involved in secret programs to develop a Wunderwaffe, a new type of weapon supposed to change the course of World War II.