Fortified Sector of Haguenau

Interior of Schoenenbourg with electric train

22nd Fortress Infantry Regiment (164e Régiment d'Infanterie de Forteresse (RIF)), Lt. Colonel Lemai, followed by Chef de Bataillon Fabre in May 1940, command post in the Bois de Kirschpiel.

• Ouvrage Hochwald, gros ouvrage E 700/O720 of eleven combat blocks with nine detached casemates. Hochwald is effectively a complex of two connected gros ouvrages, and with Ouvrage Hackenberg is one of the two largest Maginot ouvrages.
• Ouvrage Schoenenbourg, gros ouvrage O 800 of six combat blocks
• Ouvrage de Bremmelbach, proposed petit ouvrage, completed as the linked casemates Bremmelbach Nord and Sud

Peacetime barracks and support:

• Casernement de Drachenbronn[1] (now Drachenbronn Air Base, incorporating portions of Hochwald)[8]

79th Fortress Infantry Regiment (79e Régiment d'Infanterie de Forteresse (RIF)), Lt. Colonel Rethoré, command post at position 1416, then the Abri du Bucholzberg from 17 June 1940.

• Ouvrage Moulin d'Hunspach, proposed petit ouvrage, completed as the casemates Moulin d'Hunspach Nord and Sud
• Ouvrage Bois d'Hoffen, proposed petit ouvrage, completed as the casemates Hoffen Est and Bois d'Hoffen
• Ouvrage Oberroeden, proposed petit ouvrage, completed as casemates Oberroeden Nord and Est

Peacetime barracks and support:

• Casernement de Bockange[1]

Casemate d'Heidenbuckel

23rd Fortress Infantry Regiment (23e Régiment d'Infanterie de Forteresse (RIF)), Lt. Colonel Lefèvre, command post at Soufflenheim.

• Ouvrage Kauffenheim, proposed gros ouvrage, completed as casemate Kauffenheim[9]

Peacetime barracks and support:

• Casernement de Soufflenheim[1]

Casemate d'Auenheim Sud

68th Fortress Infantry Regiment (68e Régiment d'Infanterie de Forteresse (RIF)), Lt. Colonel Blanloeil.

• Ouvrage Auenheim, proposed gros ouvrage, completed as casemates Auenheim Nord and Sud[9]

Peacetime barracks and support:

• Casernement d'Oberhoffen
• Casernement de Beinheim[1]

70th Fortress Infantry Regiment (70e Régiment d'Infanterie de Forteresse (RIF)), Lt. Colonel Schwartz, then Raynaud from April 1940. Transferred from the SF Lower Rhine 5 March 1940.

CEC = Compangnie d'Équipage de Casemates, or "casemate company"

Peacetime barracks and support:

• Casernement de Gambsheim[1]

Hochwald was the first ouvrage to fire on the Germans on 8–9 September 1939 during the Phoney War, supporting French forces involved in the Saar Offensive. A number of problems with ammunition and weaponry were revealed by this action, and compatibility problems with guns and ordnance persisted into 1940 in other locations. Hochwald and Schoenenbourg fired their 75mm guns again on 16 October Hochwald fired again in November on Germans laying a minefield.[10] At Schoenenbourg a 120mm gun exploded during target practice in March 1940.[11]

The full German offensive opened on 10 May 1940. German attention was concentrated on Belgium and the Ardennes region, breaching a weak point in French frontier defenses at Sedan. The main Maginot Line was not directly attacked. However, as disaster overtook the French field armies, the interval troops were pulled out of the Line on 15 June in the central Line, but remained in the SF Haguenau.[12] Having broken through at the Sarre, German troops moved behind the Line, heading east. Hochwald and Schoenenbourg came under aerial and artillery attack on 19 June, continuing the next day. Hochwald supported Lembach with its 75mm guns when the latter came under infantry attack, but the German 215th ID broke through a weakly fortified section of the Line west of Lembach in the SF Vosges. On 21 June a German 420mm mortar and a 355mm weapon began shelling Schoenenbourg, causing some damage but not breaching the position.[13] Schoenenbourg received the heaviest bombardment of any Maginot fortification, comprising 160 aerial bombs, 50 42 cm shells, 33 28 cm shells, and approximately 3000 smaller projectiles,[14]

In early June in the face of the German assault, all fortress units attached to the Fifth Army were ordered to prepare for withdrawal to the south and west. While fortress units under the 2nd, 3rd and 8th Armies received categorical instructions to prepare to sabotage their positions and conduct an orderly retreat from 14 to 17 June, Fifth Army commander General Bourret's instructions to the SFs Rohrbach, Vosges, Haguenau and Lower Rhine were not as definitive. The personnel of the SF Haguenau were to be consolidated into a Division de Marche entitled the DM Regard, consisting of the I/22, II/23, XXI/23, I/68, II/68, II/70, II/79 and III/79e RIFs, along with the 69e RAMF and the 156e RAP. A partial withdrawal of fortress troops took place in the SF Haguenau, with some battalions of each fortress infantry regiment remaining in their positions until the armistice to cover the withdrawal of the interval troops and the fortress infantry assigned to the divisions de marche.[15]

None of the major positions in the SF Haguenau were captured by German forces prior to 25 June armistice.[16] However, by 20 June the town of Haguenau to the rear of the Line had been captured by the German 215th Infantry Division, part of a German strategy to secure the Pechelbronn oilfield.[17] To support the 215th ID, the German 246th Infantry Division was ordered to directly attack the SF Haguenau from the north. On the 20th the 246th attacked several casemates centering on Oberroeden Nord and Aschbach-Ouest and Est. Aerial bombing hit Oberroeden Nord and the Abri de Hoffen, disrupting communications but not seriously harming French defenses. German artillery hit an embrasure at Oberroeden Sud, killing one French soldier. Despite the intensity of the attack, the casemate line, aided by Hochwald and Schoenenbourg, held. The 246th withdrew with sixty-two killed, ten missing and about three hundred wounded.[18]

The Second Compiègne armistice took effect on 25 June, stopping the fighting. The final surrender of Hochwald, Schoenenbourg and their lesser positions was effected on 1 July 1940, in accordance with the terms of the armistice.[19][20] Hochwald had fired 19,550 of the 75mm, 135mm or 81mm rounds of the 90,315 on hand; Schoenenbourg 16,474 of 34,260.[21][22] Under German occupation in 1940, Schoenenbourg was subjected to a new bombardment, filmed for propaganda purposes.[23] In 1944 Hochwald (Werk Hochwald) was used as an underground factory.[24]

The 22nd RIF was deployed in the Pechelbronn area. The unit's first battalion was ordered to withdraw from the fortified line on 14 June as part of the DI Regard, falling back to Lure, then Héricourt to control the Besançon-Belfort road. The battalion was captured at Héricourt on 19 June. The other units of the 22nd RIF remained in their fortifications and surrendered on 1 July.[25]

The 23rd RIF was stationed in the Soufflenheim sub-sector. The sub-sector experienced bombardments beginning 14 May, with direct assault finally beginning 13 June, at the same time as orders arrived to detach the second and 21st battalions to the DF Regarde. The second battalion was sent to Vesoul, then to Lure, while the 21st was ordered to Sainte-Croix-aux-Mines and the Col de Sainte-Marie. The battalions saw action at several locations in the Haute-Saône before finally being captured on the 25th in the Vosges. The first battalion and CEC (compagnie d'équipage de casemates) 5 and 6 remained in their fortifications to surrender on 2 July.[26]

The 68th RIF occupied the sub-sector of Sessenheim. From 14 June the first and second companies were attached to the DF Regard and were assigned to guard the rail line between Épinal and Vaivre, the first company assigned to an area near Vesoul, and the second at Sainte-Marie-aux-Mines. Both were captured between 19 and 22 June. The third battalion, left behind in the casemates, repelled attacks on 16 and 17 June and surrendering on 30 June.[27]

The 70th RIF occupied the Herrlisheim sub-sector. Transferred from the Lower Rhine to the Haguenau sector on 5 March 1940, the regiment lost its first and second battalions to the 70/79 régiment de marche on 13 June. The formation was integrated into the 103rd DIF (the former SF Lower Rhine) and moved to Plaine and Diespach. After the armistice the units moved to Salm and were captured on 25 June. The casemate garrisons became part of the so-called groupement Schwartz after the sector's commander, and were repositioned to face to the south in the direction of the German 215th ID's threat. The garrison units surrendered on 2 July.[28]

US soldiers at Hochwald in 1944

While the Haguenau positions played little role in Allied advances in 1944, the retreating Germans caused significant damage to Hochwald, blowing up turrets, entrance blocks and several combat blocks before abandoning the position.[29] Somewhat later, in 1945, Schoenenbourg and nearby casemates Schmeltzbach Ouest, Drachenbronn Nordand Sud and Bremmelbach received the same treatment from the German 245th ID before the American 36th Infantry Division took possession. In the Alsace Plain Ingolsheim Nord and Ouest, Hunspach Village, Seltz and others were blown up.[30]

The eastern portion of the sector was the scene of heavy fighting in January 1945 as a result of the German Operation Nordwind offensive aimed at the recapture of Strasbourg. German forces of Army Group G attacked the U.S. 7th Army and French First Army. American units retreated south to the casemate line and dug in, holding on from 8 January to 21 January, before falling back to Haguenau.[31]

Following World War II, the French military reclaimed the Maginot Line with the aim of renovating and improving it against a possible attack by Warsaw Pact forces. The strongest positions, Hochwald and Schoenenbourg were grouped with Four-à-Chaux and Lembach from the SF Vosges. They were designated the môle de Haguenau ("breakwater") in 1951 and were placed back into service after a period of rehabilitation. After the establishment of the French nuclear strike force, the importance of the Line declined, and maintenance ceased in the 1970s, with most of the casemates sold.[32]

in 1956, Hochwald was transferred to the French Air Force for use as an air defense command center. New underground galleries were built in the rear (i.e., near the entrance blocks). The nearby Caserne de Drachenbronn became the above-ground support and operations facility.[33] The complex was briefly known as Ouvrage H before its designation as Base Aérienne 901 Drachenbronn.[34]