I. "Gruppe" of JG 234 was created on 15 March 1937 at Cologne Butzweilerhof Airfield. Its first commander was "Hauptmann" Walter Grabmann, who handed over command to "Major" Gotthard Handrick on 11 September 1938. The "Gruppe" was initially referred to I.("leichte Jäger") "Gruppe" and was equipped with the Heinkel He 51 B and started receiving the first Messerschmitt Bf 109 B series in May 1938. In parallel, II. "Gruppe" of JG 234 was formed in Düsseldorf. This "Gruppe" had numerous commanders during its creation phase, "Major" Werner Rentsch (15 March – May 1937), "Major" Werner Nielsen (May – 31 July 1937), "Oberstleutnant" Eduard Ritter von Schleich (1 August 1937 – 30 September 1938), "Hauptmann" Werner Palm (1 October 1938 – 27 June 1939) and "Hauptmann" Herwig Knüppel, who took command on 28 June 1939.