The Fortified Sector of the Jura (''Secteur Fortifiée du Jura'') was the French military organization that in 1940 controlled the French frontier with Switzerland in the general area of Besançon. The area was lightly fortified, since the Swiss border was regarded as a low-risk frontier, save for the possibility of an advance from Germany through Switzerland into France. The

Jura Mountains The Jura Mountains ( , , , ; french: Massif du Jura; german: Juragebirge; it, Massiccio del Giura, rm, Montagnas da Jura) are a sub-alpine mountain range a short distance north of the Western Alps and mainly demarcate a long part of the Frenc ...

and the

Doubs River The Doubs (; frp, Dubs; german: Dub) is a river in far eastern France which strays into western Switzerland. It is a left-bank tributary of the Saône. It rises near Mouthe in the western Jura mountains, at and its mouth is at Verdun-sur-l ...

presented natural barriers to invasion, allowing defenses to concentrate on a few points of potential access. The SF Jura was bordered on the east by the

Fortified Sector of Montbéliard The Fortified Sector of Montbéliard (''Secteur Fortifié de Montbéliard'') was the French military organization that in 1940 controlled the section of the French border with Switzerland in the vicinity of Montbéliard. The Montbéliard sector st ...

.Mary, Tome 1, p. 15

Concept and organization

The sector's chief fortifications were old Séré de Rivières positions like the Fort de Joux, Fort de Larmont and the Fort Saint-Antione. A late effort in 1939-1940 constructed the CEZF Line, consisting of two sections of casemates. The northern section around Morteau consisted of four casemates, of fourteen proposed. The southern section around Pontarlier consisted of three completed of six casemates proposed. Road barriers were built at

Goumois Goumois () was a municipality in the district of Franches-Montagnes in the canton of Jura in Switzerland. On 1 January 2009, the formerly independent municipalities of Goumois and Les Pommerats merged into Saignelégier Saignelégier () is ...

, La Goule, Biaufond and La Rasse. Crossings of the Doubs were fortified at Villiers-le-Lac, Morteau, Pont-de-la-Roche and

La Cluse La Cluse (Vivaro-Alpine: ''La Clusa'') is a former commune in the Hautes-Alpes department in southeastern France. On 1 January 2013, Agnières-en-Dévoluy, La Cluse, Saint-Disdier, and Saint-Étienne-en-Dévoluy amalgamated into the new commune ...

Command

The Jura sector was under the command General Huet, commanding a demi-brigade of ''chasseurs pyrénéens''. From 15 January 1940 the Jura Army Corps (''corps d'armée du Jura'') took responsibility for field operations in the Jura. Within ten days it was renamed the 45th Army Fortress Corps (''45e corps d'armée de foretresse''). The corps comprised the 57th Infantry Division under General Texier, and the 63rd Infantry Division under General Parvy. Both were class B reserve divisions, not suitable for heavy or sustained combat. The SF Jura was attached to the 45th CAF on 16 March 1940. Until 19 May, the 45th CAF was an autonomous unit. Afterwards it was attached to the 8th Army.Mary, Tome 3, p. 146 At the midpoint of the Battle of France on 1 June 1940, the fortress troops of the SF Jura amounted to a ''chasseurs pyrénéens'' regiment in three battalions, comprising 85 officers and 2,750 men.Mary, Tome 3, p. 189

Battle of France

The German offensive (Operation ''Kleiner Bär'') across the Rhine was concentrated in the area near and to the north of

Colmar Colmar (, ; Alsatian: ' ; German during 1871–1918 and 1940–1945: ') is a city and commune in the Haut-Rhin department and Grand Est region of north-eastern France. The third-largest commune in Alsace (after Strasbourg and Mulhouse), it is ...

, with little fighting in the Altkirch sector. The offensive, launched on 15 June, was rendered unimportant when the German XIX Corps under General Heinz Guderian reached the Swiss border on 17 June, behind the main French line.Mary, Tome 3, p. 200 Guderian approached the SF Jura from the rear, crossing the Doubs at

Saint-Vit Saint-Vit () is a commune in the Doubs département in the Bourgogne-Franche-Comté region in eastern France. Geography The town lies northwest of Boussières. Population See also * Communes of the Doubs department The following is a list ...

near Besançon. German advance parties reached the Swiss border near Pontarlier.

References

Bibliography

*Allcorn, William. ''The Maginot Line 1928-45.'' Oxford: Osprey Publishing, 2003. *Kaufmann, J.E. and Kaufmann, H.W. ''Fortress France: The Maginot Line and French Defenses in World War II'', Stackpole Books, 2006. *Kaufmann, J.E., Kaufmann, H.W., Jancovič-Potočnik, A. and Lang, P. ''The Maginot Line: History and Guide'', Pen and Sword, 2011. *Mary, Jean-Yves; Hohnadel, Alain; Sicard, Jacques. ''Hommes et Ouvrages de la Ligne Maginot, Tome 1.'' Paris, Histoire & Collections, 2001. *Mary, Jean-Yves; Hohnadel, Alain; Sicard, Jacques. ''Hommes et Ouvrages de la Ligne Maginot, Tome 3.'' Paris, Histoire & Collections, 2003. *Mary, Jean-Yves; Hohnadel, Alain; Sicard, Jacques. ''Hommes et Ouvrages de la Ligne Maginot, Tome 5.'' Paris, Histoire & Collections, 2009. *Romanych, Marc; Rupp, Martin. ''Maginot Line 1940: Battles on the French Frontier.'' Oxford: Osprey Publishing, 2010.

External links

Jura (secteur défensif du)
at fortiff.be
Le Secteur Fortifié du Jura
at Wikimaginot.eu {{DEFAULTSORT:Jura, Fortified Sector Of The French border defenses before World War II