The Atlantic Wall (1): France

PRINCIPLES OF DEFENSE

Like many of Hitler’s personal passions, the Atlantic Wall was a half-baked scheme. The gnat bites by British Commandos along the French and Norwegian coast provoked Hitler into a massive construction completely out of proportion to its tactical value. Hitler had a visceral enthusiasm for monumental fortification after his experiences as a young infantryman in the trenches in World War I. Ironically, it was the Wehrmacht that had demonstrated the futility of linear defenses against the combined power of mechanized firepower and air attack. Furthermore, the Atlantic coast was so long that it was impossible to create any defense-in-depth with the Atlantic Wall, inevitably resulting in a weak and vulnerable configuration. As Frederick the Great had remarked: “who defends everything, defends nothing.”

German military commanders had mixed feelings about the Atlantic Wall concept. Few commanders believed that the Atlantic Wall could repulse a serious Allied invasion, but many at the same time felt that some degree of fortification was worthwhile given the poor quality of the troops assigned to coastal defense. At the heart of this controversy was the poor fit between the Atlantic Wall fortification schemes and army tactical doctrine. This is evident when examining the German tactical response to Allied amphibious attacks in the Mediterranean Theater in 1943–44. Rather than tie down vast resources in a linear defense of the Italian coast, the Wehrmacht did not immediately contest the landings at Sicily, Salerno and Anzio. Instead, once the landings had taken place, the German commanders mobilized their mechanized forces and staged a violent counterattack against the bridgehead.

When von Rundstedt was appointed to head OB West (Supreme Command West) in the spring of 1943, he ordered a comprehensive inspection of the Atlantic Wall defenses which took place from May to October 1943. The problem was not so much the uncompleted Atlantic Wall as the continuing drain of resources out of France to the Russian Front. The infantry divisions stationed in France were second-rate static divisions, which were hardly adequate for positional defense. The continued decline in troop quality in 1943 was somewhat offset by continuing fortification of the coast, since it was widely believed by German commanders that the poor-quality troops would be more likely to resist from the safety of bunkers than from exposed field positions.

^{Beach defenses along the Atlantic Wall frequently included anti-tank walls to prevent easy access off the beach. This example on Oye-Plage east of Calais has sunken over the years but shows an interesting example of an improvised machine-gun bunker built into the corner of the walls. (Author’s collection)}

Under the circumstances, OB West attempted to meld accepted tactical doctrine with the Atlantic Wall fortifications. The resulting tactics were dubbed “crust—cushion—hammer.” The Atlantic Wall was the crust that would stop or delay the initial Allied invasion and give the army time to move its mobile reserves into action. The cushion was the coastal region immediately behind the Atlantic Wall, which would be covered by proposed “Position II” defenses. This was a half-hearted attempt started in November 1943 to provide some defense-in-depth to the Atlantic Wall through a series of field emplacements. Since there was not enough concrete, construction was limited to earthen defense works. In the event, Position II never emerged as a serious defensive program due to Rommel’s insistence that the emphasis be placed on the initial “crust” of the Atlantic Wall. The “cushion” of the coastal belt also served as a buffer zone since the Panzer commanders did not want to conduct operations near the beaches within the range of Allied warships based on the lessons of the Mediterranean Theater, where Panzer attacks were repeatedly demolished by naval gun fire. The “hammer” was the OB West reserve, primarily Panzer Gruppe West under the command of General Freiherr Leo Gehr von Schweppenburg.

^{A fairly typical example of beach obstacles in the Fifteenth Army sector east of Dunkirk in September 1944. The obstacles in the foreground are Nussknacker (nutcrackers) made from French artillery projectiles with a pivoting steel trigger designed to blow up under landing craft or tanks. Closer to the sea are a variety of obstacles, mainly wooden tetrahedrons but also some steel Czech hedgehogs. (NAC P-174349 Ken Bell)}

OB West grew increasingly worried in early autumn of 1943 due to Allied deception plans such as Operation Starkey, which suggested an invasion against the Pas-de-Calais could happen at any moment. A pungent view of the state of the Atlantic Wall at this time was provided by a letter from the Fifteenth Army commander, Gen.Obst. Hans von Salmuth, to Gen. Jodl of the OKW staff in Berlin:

^{One of the more common types of obstacles deployed in 1944 was a simple post obstruction enhanced by adding a Teller mine on top to blow a hole in the bottom of landing craft. In reality, such mines failed as often as not due to the effect of frequent submersion in seawater, symptomatic of Rommel’s slap-dash obstacle program, which argued that “something was better than nothing.” (NARA)}

^{This M262 fire-control bunker of MKB Vasouy of 9./MAA.266 was positioned on the Seine River opposite Le Havre. It is typical of naval fire-control posts, with an observation post below and a rangefinder post above. (Author’s collection)}

With the threat of an Allied invasion of France increasing, even Hitler realized that the Western Front could no longer be ignored. His first action in the autumn of 1943 was to appoint Generalfeld-marschall Erwin Rommel to command the new Army Group for Special Employment (later Army Group B) to direct the invasion front. Hitler also authorized Führer Directive 51 on November 3, 1943, that on paper at least reoriented the strategic priorities for resources and ordered that additional steps be taken to reinforce the Western Front due to the likelihood of Allied invasion sometime in 1944.

Rommel approached his new assignment with characteristic vigor and began a tour of the defenses starting in Denmark in December 1943 and working his way down the French coast in early 1944. He came to this new command with a different perspective than most senior Wehrmacht commanders, having spent the past several years fighting the Allies in the Mediterranean Theater rather than the Red Army on the Russian Front. His last assignment had been the command of German forces in northern Italy. While this did not directly involve him in combating recent Allied amphibious assaults in Italy, he had been involved in the debates over the best approaches to repel the Allied landings. In the case of both Sicily in July 1943 and Salerno in September 1943 the Wehrmacht in Italy had followed the accepted doctrine but it had failed to crush the landings. In both cases, the Allied landings were initially unopposed but Panzer forces were promptly mobilized and the beachhead attacked in force. In both cases, the mechanized attacks were stopped cold by a combination of tenacious Allied infantry defense stiffened by a suffocating amount of naval gunfire. During the course of his inspections along the Atlantic Wall, the Allies launched yet another amphibious attack against Anzio in January 1944 and, once again, the German mechanized counterattacks in February 1944 failed with heavy losses. This only served to reinforce his doubts about the current tactics for dealing with Allied amphibious attacks.

Rommel’s iconoclastic views extended to other aspects of the defensive plans. German planning assumed that the most likely location for the Allied invasion would be on the Pas-de-Calais. This was the narrowest point of the English Channel and was close enough to Britain that the invasion force could be supported by fighter aircraft based in southern England. It also offered better prospects for approaches into Germany compared to the soggy lowlands of Holland or the hilly forests of the Belgian–German frontier. As a result, the Atlantic Wall defenses as well as troop dispositions were far denser on the Pas-de-Calais than on any other stretch of the French coast. Yet the fact that it was such an obvious choice led Rommel to wonder whether another location might be more likely. Von Rundstedt and the senior commanders remained convinced that the Allies would strike at or near a port. They had done so at Salerno and Anzio, but the landings at Sicily made it clear that they could conduct an amphibious landing without a port.

^{Stützpunkt 164, between Cap Gris-Nez and Cran aux Ouefs, was the site of MKB Tilly of 5./MAA.244 with two M270 casemates armed with 150mm guns. The three large pillars near the casemate are the V143 base for a massive Mammut surveillance radar that supported the neighboring Batterie Todt and other heavy gun batteries in the area. (Author’s collection)}

Rommel became convinced that new approaches were necessary. From a tactical standpoint, he rejected the current doctrine and argued that instead of defense in depth with the Panzer divisions kept in reserve away from the beaches, all available resources should be moved as close to the likely landing areas as possible. He believed that the Italian campaign had demonstrated that if the invasion could not be stopped immediately, it could not be stopped at all. He also questioned whether the Allies would actually strike at a port. A landing some distance from a port could lead to the eventual envelopment and capture of the port. In spite of Rommel’s considerable influence with Hitler, his views were not widely accepted by senior German commanders in France. The debate over the best approach to deploying the Panzer divisions continued right up to D-Day and was not settled to the satisfaction of either side in the debate.

From the perspective of the Atlantic Wall, Rommel’s leadership had several important consequences. Rommel invigorated efforts to defend the beaches between the major ports, especially along the Pas-de-Calais and Normandy. By early 1944, the Kriegsmarine had received the bulk of Organization Todt’s resources and the ports had been well fortified. More attention had to be directed to the army’s shoreline defenses. Besides enhancing the fortifications along the coast, Rommel suggested that more attention had to be paid to extending defenses out on the beaches. His own experiences in the desert campaign had convinced him of the value of mine warfare and obstacles. Rommel argued that by creating obstructions along the coast, amphibious landing craft would be prevented from reaching the shelter of the shoreline. In combination with enhanced beachfront fortifications, this would create a killing zone along the shoreline. Instead of landing near the protective seawalls so common on the Channel coast, the infantry would have to disembark hundreds of meters from shore, exposed to prolonged fire as they attempted to reach the sanctuary of the shoreline. In contrast to his arguments about defensive tactics, Rommel’s recommendations for improved coastal defense were welcomed by von Rundstedt and the other senior commanders who felt that the army had been too long neglected in the Atlantic Wall construction compared to the Kriegsmarine.

Rommel’s intervention came at an opportune time for the fortification program. The pace of construction of the Atlantic Wall had fallen off from its highpoint in April 1943 to its lowest point in January 1944 when less than half as much construction was completed. While some of this decline was seasonal, other factors were more important. On the night of May 16/17, 1943, the RAF had breached several of the Ruhr River dams, flooding a portion of Germany’s industrial heartland and knocking out hydroelectric power generators. Speer pledged to Hitler that the Organization Todt would clean up the mess as quickly as possible, and so resources were drained out of the Atlantic Wall program through much of the summer of 1943. Hitler’s new fancy in the autumn of 1943 was the forthcoming V-weapon program, and a major construction effort was begun by the Organization Todt in Normandy and the Pas-de-Calais to create launch sites for the missiles, further undermining the fortification effort. Finally, the pre-invasion Allied air campaign was aimed at crippling the French rail and road networks, and through the late winter and early spring of 1944, Organization Todt workers were diverted from fortification programs to assist in rebuilding the railroads.

^{This Rheinmetall 150mm SKC/28 in a coastal C/36 mount with non-standard gun-shield was one of four guns of MKB Landemer, 6./MAA 260, positioned in an M272 casemate, part of StP 230 in Castel-Vendon to the west of Cherbourg. (NARA)}

To compensate for the shortages of Organization Todt construction workers, in 1944 the Wehrmacht began to assign some of the construction work to infantry divisions along the coast. Each of the infantry corps had a Festung Pioneer Stab (Fest.Pi.Stab: Fortification Engineer Staff) assigned to it. These were organized somewhat like a regiment with three attached battalions, but these were administrative units, not tactical formations, and their principal role was to plan and direct the construction of fortifications within their sector. In the late winter and spring of 1944, they were assigned additional troops, often Ost battalions of Soviet volunteers, to help carry out construction work. The primary work assigned to the infantry troops was to assist in creating the shoreline defenses. Since resources were very limited, most of this work involved either the transfer of obstacles from idle defensive works in occupied Europe, or the creation of improvised obstacles using local resources. Cointet obstacles, also called Belgian gates or C elements, were large steel-frame devices manufactured in the 1930s to block Belgian frontier roads. Czech hedgehogs (Tschechenigelen) were collected from Czech forts in the Sudetenland as were similar obstacles found elsewhere in occupied Europe. Similar obstructions were made from scrap metal and concrete including concrete tetrahedons. One of the simplest forms of anti-craft obstruction was an angled pole, often topped by a Teller mine. During his tour of the defenses in February 1944, Rommel was shown a local technique at Hardelot-Plage using fire hoses to quickly dig holes for these stakes, and this technique was widely disseminated through France. Some of this work was too hasty and ill conceived. When some officers decided to test the effectiveness of the stakes using a British landing craft captured at Dieppe, they were shocked to find that the craft simply plowed through the obstructions with little trouble. As a result, the more substantial Hemmbalk (beam obstruction) was designed resembling a large tripod.

The most effective anti-craft device was a Kriegsmarine mine called the KMA (küstenmine-A: coastal mine-A), which consisted of a concrete base containing a 75kg explosive charge surmounted by a steel tripod frame with the triggering device. Although cheap and effective, they became available too late to be laid along the entire coastline. They were first laid along the Channel coast from Boulogne south towards Le Havre since this sector was considered the most likely to be invaded, and this phase was completed in early June 1944. The next area to be mined was the Seine estuary around Le Havre, which was to begin on June 10, but this never took place due to the invasion. Because of shortages of the KMA mine, the army developed cheap expedients, the most common of which was the “nutcracker” (Nussknacker), which consisted of a French high-explosive artillery projectile planted in a concrete base with a steel rod serving as the activating lever. Nearly 10,000 of these were manufactured and deployed in 1944.

Another change in fortification plans in early 1944 was the decision to place all field artillery of the static divisions on the coast under concrete protection, based on the lessons from the Salerno campaign. These casemates were not especially elaborate and were simple garage designs such as the H669 and H612. This program began in earnest in January 1944.

OB West was very concerned about the possibility of Allied airborne attacks, and several steps were taken to deal with this threat. Large fields near the coast were blocked with poles and other obstructions to prevent glider landings, though in practice this proved to be flimsy and ineffective. In some low-lying coastal areas such as the fields behind Utah Beach and the fields southwest of Calais, the Wehrmacht flooded the fields to complicate exit from the beach. However, many German tactical commanders were reluctant to flood valuable crop fields as local units often depended on local produce to feed their troops and this placed a limit on the extent of deliberate flooding.