In September 1939, Witzleben, now a Generaloberst (Colonel General), took command of the 1st Army, stationed at the Western Front. When Germany attacked France on 10 May 1940, the First Army was part of Army Group C. On 14 June it broke through the Maginot line, and within three days had forced several French divisions to surrender. For this, Witzleben was decorated with the Knight's Cross of the Iron Cross; and on 19 July, he was promoted to Generalfeldmarschall (General Field Marshal) during the 1940 Field Marshal Ceremony.