Fortified Region of Metz

The Fortified Region of Metz comprised the central and most heavily fortified portion of the Maginot Line. The region was established in 1926 as a military organization for the French fortifications along the frontier with Luxembourg and Germany to the east of Longuyon in northeastern France, forming a shield to the north of the industrialized areas of Metz and Thionville. The region was dissolved as a military organization on 18 March 1940, its command personnel moving to the 42nd Army Corps.

The region was divided into four sectors:

The region was given the highest priority in funding, manning and equipment of all Maginot regions.

Following the First World War, French defense policy was re-examined at the order of Marshal Philippe Pétain. The 1919 study recommended the creation of a mobile army that could carry war to the territory of an enemy, supported by frontier defenses that would prevent an enemy from penetrating French territory. The second part of the recommendation was to involve the creation of fortified regions (regions fortifiés) in which an enemy could be confronted. The initially recommended fortified regions included:

The regions were to provide locations in which to confront an enemy and from which to launch an offensive to carry the battle onto enemy territory. The Metz region was considered a potential base for a counter-offensive should border defenses be pierced and Lorraine threatened, possibly using the former German fortifications of Metz and Strasbourg. The previous fortifications of the Séré de Rivières system of the 1880s were designed to defend the frontiers of France that existed following the Franco-Prussian War, in which France had lost Alsace and Lorraine. With the recovery of these territories following World War I, most of the Séré de Rivières forts were deep in the interior of northeastern France and not useful.

The Conseil Supérieure de la Guerre ("Supreme War Council") created a committee in March 1920 to study France's newly adjusted frontiers, with Marshal Joseph Joffre as chairman. Disagreement arose between supporters of Pétain, who favored continuous light defenses covering concentrations of troops and construction materials for field fortifications, and supporters of Marshal Joseph Joffre, who advocated fortified regions like the ring of forts around Verdun, that had performed well during the first world war. The committee dissolved without reaching any conclusions.

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