Fortified Sector of Montbéliard

The Montbéliard sector stands in the vicinity of the Belfort Gap, a traditional invasion route into eastern France.

However, the area was lightly defended, as the Swiss border was not regarded as an area with a high risk of invasion, and because the left bank of the Rhine was firmly in French hands.

The Montbéliard sector was chiefly composed of old Séré de Rivières system fortifications constructed to defend the Belfort Gap.

[1] The Montbéliard sector was under the command of the Fortified Region of Belfort until 16 March 1940, when the Belfort region became the 44th Army Fortress Corps (44e Corps d'Armée de Forteresse), retaining the Montbéliard sector under its command.

[1] At the midpoint of the Battle of France on 1 June 1940, the troops of the SF Montbéliard amounted to a chasseurs pyrénéens regiment in two battalions, comprising 235 officers and 7,390 men.