Fortified Sector of Boulay

The Fortified Sector of Boulay (Secteur Fortifiée de Boulay) was the French military organization that in 1940 controlled the section of the Maginot Line to the north and east of Metz in northeastern France. The left (western) wing of the Boulay sector was among the earliest and strongest portions of the Maginot Line. The right wing, started after 1931, was progressively scaled back in order to save money during the Great Depression. It was attacked in 1940 by German forces in the Battle of France. Despite the withdrawal of the mobile forces that supported the fixed fortifications, the sector successfully fended off German assaults before the Second Armistice at Compiègne. The positions and their garrisons finally surrendered on 27 June 1940. Following the war many positions were reactivated for use during the Cold War. Three locations are now preserved and open to the public.

The Boulay sector was part of the larger Fortified Region of Metz, a strongly defended area between the Ardennes to the west and the Sarre valley to the east. The Metz region was more important during the planning and construction phase of the Maginot Line than it was in the operational phase of the Line, when the sectors assumed prominence. The Fortified Region of Metz was dissolved as a military organization on 18 March 1940.

The Boulay sector was of two natures. The left, or western wing, was as strong as any place in the Line, with Hackenberg, one of the two largest Maginot ouvrages. The right, eastern wing received a lower priority and less funding. Many of the petit ouvrages that were built were to be augmented in the second cycle of construction that was to start in 1940, receiving remote entrances, underground barracks, or links between isolated positions in addition to additional combat blocks.

The Boulay sector was under the overall command of the French 3rd Army, headquartered at Fort Jeanne d'Arc at Metz, under the command of General Charles Condé, which was in turn part of Army Group 2 under General André-Gaston Prételat. The SF Boulay was commanded by General Besse until late June 1940, then Colonel Cochinard. The command post moved several times. In May 1940 it was located at the Château Marivaux at Hayes. The interval troops, the army formations that were to provide the mobile defense for the sector, to support and be supported by the fixed defenses, were under the command of the 6th Corps (6e Corps d'Armee), General Loizeau, commander. The 6th Corps was in turn made up of the 42nd and 26th Infantry Divisions, as well as the British 51st (Highland) Infantry Division, a detached part of the British Expeditionary Force. Artillery support for the sector was provided by the 153rd Position Artillery Regiment (Régiment d'Artillerie de Position (RAP)), which controlled both fixed and mobile artillery, commanded by Chef d'Escadron Charly. The 42nd ID was made up of active-service troops, while the 26th ID was a Class A reserve formation.

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