Sixth United States Army Group The Sixth United States Army Group was an Army Group of the Allies during World War II , and as contained armies from both the United States Army and the French Army it is also referred to as the Southern Group of Armies . History . The Sixth Army Group was originally created in Corsica , France ( specifically activated on 29 July 1944 ) as " Advanced Allied Force HQ " , a special headquarters within AFHQ ( the headquarters of Henry Maitland Wilson , the Supreme Commander Mediterranean Theatre ) commanded by Lieutenant General Jacob L . Devers . Its initial role was to supervise the planning of the combined French and American forces which invaded southern France in Operation Dragoon and provide liaison between these forces and AFHQ . Dragoon was the operational responsibility of the US Seventh Army commanded by Lt . Gen . Alexander Patch . Available to Patch were three Corps ( US VI Corps and French I and II Corps ) and 24 , 000 Maquis of the " Forces Francaises de l ' Interieur " . The two French Corps constituted " French Army B " commanded by Général Jean de Lattre de Tassigny which was later renamed French First Army . Although Sixth Army Group Headquarters was officially activated on 1 August , it consisted of only the personnel of the Advanced Detachment AFHQ and , for reasons of security , retained the detachment title . The Advanced Detachment headquarters on Corsica had no command or operational duties and functioned primarily as a liaison and coordinating agency while preparing itself for the day it would become operational in France as Sixth Army Group headquarters . Devers ' headquarters remained subordinate to AFHQ during the invasion and in the weeks immediately afterwards while operational control of the troops on the ground resided with Patch until his forces linked near Dijon , France with Twelfth United States Army Group ' s Third Army advancing from the west after breaking out of the Normandy beachhead . At this time , on 15 September , Devers ' headquarters was designated Sixth Army Group to take operational control of Seventh Army and French Army B and came under the overall command of General Dwight D . Eisenhower , the Supreme Commander at SHAEF ( Supreme Headquarters , Allied Expeditionary Forces ) . In late 1944 and early 1945 the Sixth Army Group was involved in fierce fighting in the Alsace repelling the German advance during Operation Nordwind and subsequent pitched engagements closing off the Colmar Pocket . The Army Group later advanced along the Swiss Border , then through Bavaria , and eventually into western Austria . The 63rd Infantry Division was the first Seventh Army unit to cross the Siegfried Line , and the first to get an entire division through it . The 3rd Infantry Division suffered the highest casualty count of all US divisions with over 27 , 000 casualties . In the Brenner Pass , elements of Sixth Army Group linked up on 5 May 1945 with the Fifth Army advancing north from Italy . After the end of the war , part of the Sixth Army Group , the U . S . Seventh Army , remained as an occupation and defensive force in southern Germany for many decades . It also occupied part of Austria until that country was released from occupation in the mid 1950s .