[Note 1] Müller was born on 21 November 1920 in Frankfurt am Main, at the time in the Province of Hesse-Nassau within the Weimar Republic.

[3] He joined the military service of the Luftwaffe in 1938, initially serving with the Nachrichtentruppe (signal corps).

[8] In January 1942, Jagdgeschwader 5 (JG 5—5th Fighter Wing) was newly created and placed under the command of Oberst Carl-Alfred Schumacher.

Ya and Serzhant A. I. Chibsov from 20 GvIAP (Guards Fighter Aviation Regiment—Gvardeskiy Istrebitelny Aviatsionny Polk), and a Tupolev SB bomber piloted by Mladshiy Leytenant Golovanov from 137 SBAP (High-Speed Bomber Aviation Regiment—Skorostnoy Bombardirovochnyy Aviatsionny Polk)[10] On 26 April, seven Petlyakov Pe-2 bombers, escorted by fighters from the 95 IAP (Fighter Aviation Regiment—Istrebitelny Aviatsionny Polk), attacked the Kirkenes Airfield.

[8] The Allied Convoy PQ 16, consisting of 35 merchant vessels, headed from Hvalfjörður in Iceland to Murmansk from 21 to 30 May.

[12] That morning at 09:20, Müller, Leutnant Heinrich Ehrler, Unteroffizier Hans Döbrich and another pilot each claimed a Hurricane fighter shot down.

At the time and in the same area of this encounter, Podpolkovnik (lieutenant colonel) Boris Safonov, commander 2 GvSAP of the Soviet Naval Aviation, was shot down in his Curtiss P-40 Warhawk and killed in action.

The presentation was made by Generaloberst Hans-Jürgen Stumpff at Petsamo, present-day Pechenga in Murmansk Oblast.

[17] During aerial combat near Murmashi on 21 August, his Messerschmitt Bf 109 F-4 trop (Werknummer 10073—factory number) was hit, resulting in an emergency landing at the Petsamo airfield.

Müller injured his leg in a skiing accident in December that year, and after recovery was granted leave in Germany, returning to his unit in February 1943.

[19] On 19 April 1943, Müller was shot down in his Bf 109 G-2 (Werknummer 14810) by a Hurricane from 609 IAP, and was captured by Soviet forces.

[21] On 21 October 1943 Müller was shot during an escape attempt at Temnikov, while being moved to a camp in Mordovia.