To what extent did the Nazi military’s superior strategy secure a German victory during the Battle of France in 1940?

Following the outbreak of World War II with the invasion of Poland on 1^st September 19391 , the Allied powers of Britain and France would declare war on Germany. Hitler’s eventual vision was the prevention of the Western Powers from being able to oppose the state consolidation and development of the Germans, partially consisting of an invasion of France. From 10^th May 1940 to 25^th June 1940, Hitler’s planned invasion of France occurred, gaining notoriety due to the rapid fall of France within six weeks. Many historians consider the defeat as the most humiliating disaster in French history and describe it as the most sweeping victory for the Germans. The erratic nature of the defeat has sparked debate among historians over the primary cause of the fleeting German conquest.

One of the prevailing narratives argue that the German military strength was the main reason for German victory at the Battle of France. However, these strengths can be separated into various factors. For example, their strengths may have originated from Germany's strategy, a view supported by historians Karl-Heinz Frieser and John T. Greenwood in their publication, The Blitzkrieg Legend the 1940 Campaign in the West.

Another view is that superior German tactics may have been the key factor in their victory. The concept of Blitzkrieg is highlighted throughout as a crucial centerpiece in Nazi military tactics, with Alan S. Milward being the most prominent advocate. Part of such tactics involved the incorporation of the Luftwaffe, with historians such as John Buckley, dedicating a section of his book Air Power in the Age of Total War to the Luftwaffe and its significance. Buckley emphasizes its purpose to complement German land forces in specialised Panzerwaffe units during their campaigns through the Low Countries, an operation dubbed Fall Gelb (Case Yellow).

To gain insight into the successes of the German army, this investigation employs several primary sources such as Hitler’s war directives from 1939 and early 1940. While brief, it effectively summarizes Hitler’s decision to invade France and indicates strategic expertise through their plans to attack Belgium and Holland to flank the French behind the infamous Maginot Line.

On the other hand, the alternative stance addresses the failures of the French army and government. Secondary sources include Ernest R. May’s Strange Victory: Hitler's Conquest of France, Robert A. Doughty’s The Breaking Point: Sedan and the Fall of France, 1940 and Joel Blatt’s The French Defeat of 1940, Reassessments. French failures span all aspects, from inadequate training to questionable leadership, particularly from the enigmatic general Maurice Gamelin, whose reliance on the Maginot Line exposed his outdated generalship.

Primary sources used to understand the flaws within every level of the French military hierarchy include Memoires De Guerre, a biography by eventual French president Charles de Gaulle, and retrospective accounts by other French generals, most prominently Marshal Petain who had been appointed leader of the Vichy puppet state following their defeat.

In order to determine which factor was most crucial to the fall of France in 1940, this essay will be exploring “To what extent did the Nazi military’s superior strategy secure a German victory during the Battle of France in 1940?”

Firstly, the Germans’ development of a compelling attack strategy, dubbed Fall Gelb, was the primary reason for their victory. Historians who argue for this sentiment include Karl - Heinz Frieser and John T. Greenwood. To begin, the adoption of a compelling strategy was essential since German motor and technological strength were still lacking compared to other European powers. As a comparison, the French had 300000 vehicles mobilized in 1940 against the 120000 vehicles of the Germans. This was made more apparent when considering that only 16 of the 157 German divisions were fully motorized in 1940, a mere 10%. Furthermore, the Werhmarcht had infantry carrying weaponry that were severely outdated, some even using machine guns from the World War 1 era. Therefore, the Germans could not rely on sheer force to defeat the French.

The military strategy was initially partly adopted from the famous Schlieffen Plan during the Great War. This maneuver eventually allowed the Germans to create a weak point in the French defence between Namur and Sedan, the Ardennes region which they would exploit. This strategy was mostly aptly presented in Hitler’s 6th directive on the 9 October 1939, where it was to be conducted through “The northern flank of the western front, through Luxembourg, Belgium, and Holland. The value of this strategy was avoiding the heavily fortified Maginot Line, reducing the chance of a full scale conflict as the purpose of the line was to stall and subsequently repel an oncoming German assault.

One reason German strategy was crucial in the victory was the German’s ability to adapt the strategy on numerous occasions, hastening the date at which the invasion could occur. Franz Halder, Chief of the General Staff of the Oberkommando des Heeres (OKH), condemned the rash invasion of France in 1939 against the Fuhrer's ambitions. Instead, Franz Halder developed Fall Gelb (Invasion plan for France). Frieser believed that without the Germans’ caution when formulating their strategy, an invasion of France would have been detrimental, as their military forces had been exhausted from invading Poland. This meant that if they wanted to carry out Fall Gelb in 1940, while their forces were not prepared, they had to be flexible in their development. Their adaptability was showcased through a proposal by Wehrmacht commander Erich von Manstein in early 1940, which included a diversion in Belgium to isolate the strongest Allied divisions before thrusting through the South, shifting the possibility of the invasion to May 1940. The reason why this allowed for the advancement of the invasion was because it lured Allied forces out of France, without which, the German forces would not be able to take on the Allies on their home soil until at least 1942. By advancing plans, the Germans could exploit the French army’s unsatisfactory preparations and training since they required time to be resolved, allowing Germany to capitalize their advantages over the French. Thus, the flexibility of Fall Gelb contributed to a German victory as it enabled an invasion to occur sooner than expected when France was in a more vulnerable state.

Aside from its flexibility, Fall Gelb itself was also an ingenious plan that outmaneuvered the French, leading to a German victory. Even with the Germans striking their enemies during a period of unpreparedness, this by itself was not sufficient, with the deception strategies that they employed also being essential. Referring to Figure 1, the final iteration of Fall Gelb shows how the Wehrmacht’s movement is evidently altered, with the most obvious change being the bulk of the forces flanking Belgium from the south. The Germans carried out this variation of the attack on the 10^th of May. Referring to the side boxes in Figure 1, Group B who were composed of relatively weaker divisions that acted as the ‘matador’s cloak’, was sent to attack Holland, luring the majority of the Allied forces away from France. However, Group A had advanced Panzer divisions and had their quantity of divisions increased from 22 to 45. Their role was to remain cautiously concealed to increase the potency of their ambush through the weak Ardennes, encircling any Allied forces. Group C was to remain east of Luxembourg and served the role of occupying the French forces along the Maginot Line, disrupting the diversion of Allied troops to Belgium. This plan succeeded, evidenced by French Generals Gamelin and Georges believing the Germans had sent their main forces through Holland and Belgium.

Moreover, Hitler had also acknowledged the importance of this diversion in their successes in his 11th directive where he mentions “He (Allies) continues to throw strong forces against the line Namur-Antwerp and appears to be neglecting the sector facing Army Group A”. The significance of the diversion succeeding was that Group A managed to venture through the Ardennes and flank the majority of the Allied forces. The loss in Allied forces were immense, with only one out of their seven motorised divisions escaping the encirclement and a majority of their cavalry divisions destroyed. This allowed for the Germans to win the battle even before reaching France as all of the Allies’ strongest forces would be decimated, leaving a vulnerable France that was easily rampaged. The loss to France was exemplified by French Lieutenant Cameron, who commented that the French troops were “filled with a sense of finality and death; the curtain was raining down on a great tragedy.” Therefore, Frieser believes that meticulous strategic planning done by the Germans had allowed them to cripple the Allied forces to a point which left France vulnerable, leading to Germany’s triumph merely weeks later.

However, while the strategic brilliance of Fall Gelb was pivotal to Germany’s victory, its importance may have been overstated by Frieser. First, Frieser’s work is limited by its origin and content, as Frieser was a German historian who based his research largely on German Federal Military Archives, implying that the argument he presents would be based primarily on Germany’s strengths, while neglecting the role of France in their own defeat. Furthermore, the source is also limited based on purpose, as its main objective was to debunk the myths surrounding Blitzkrieg whilst highlighting the importance of Fall Gelb. This may raise the concern that the arguments are not entirely objective. Nevertheless, his work is valuable based on its content since it does underscore the importance of German strategy, with several chapters dedicated to the topic which contained sufficient information to argue for the significance of German strategy. Further, it is also valuable based on origin, as although the work had been translated from Frieser’s native language of German, the editor had worked closely with Frieser throughout the translation to ensure that the nuances of the German and English languages does not alter the argument. Hence, despite his work’s limitations, Frieser’s view that superior German strategy was paramount in their victory was credible.

Besides German strategy, the German tactics, namely Blitzkrieg, or ‘Lightning War’, was heavily utilized to beat the French using speed rather than raw strength. Frieser defines the tactic as “the concentrated employment of armor and air forces to confuse the enemy with surprise and speed and to encircle him”. In Frieser’s work, he cites Alan Milward being an advocate for it, while Jeffery L. Ethell and John Buckley argue for the Luftwaffe’s involvement in Germany’s victory, which was a crucial component of Blitzkrieg. While the strategic prowess Fall Gelb was important, it had to be complimented with quick penetration of the Allied defenses55 to ensure their forces would not be made “easy targets” and be picked off in their risky maneuvers. The importance of Blitzkrieg can be summarized by Frieser’s opinion that “the nature of war was revolutionized” by it.

Notably, Blitzkrieg was critical during the invasion of the Low Countries, allowing the Germans to capture territory from the Dutch and Belgians by 28th May, hastening the Allied retreat during Operation Dynamo. The phenomena can be seen during several of the conquests, a notable one being during the Battle of Sedan which occurred from the 12th to 15th of May 1940. Going on the offensive, Group A forces crossed the Meuse river that separated the two opposing sides which threatened to outflank the Allies. This forced the already weak French defensive line retreating backwards towards Waterloo, all part of a larger offensive into Belgium, which in itself could be classified as a Blitzkrieg tactic. Without the rapid advancement of the German primary divisions into Belgium, the encirclement of the Allies would have been an arduous process since the French could relocate their forces to Sedan in four days and would have been able to compromise Fall Gelb. The importance is further underscored by German General Staff Officer Kielmansegg’s comment on the situation “the whole thing would fail because the French would now realize that the main effort was here.” Hence, the Germans’ approach to the invasion through rapidness displays Blitzkrieg’s critical role.

Additionally, part of the effectiveness of Blitzkrieg was the tactical organization of Panzer Divisions, which were also crucial in their victory during the early stages of the invasion. They revolved around tanks, with Germany’s 2900 tanks distributed into 10 Panzer Corps. This was especially important as they were at an armament disadvantage and had to maximize the limited functionality of their tanks. Briefly, these divisions were centered around a core of tanks, surrounded by other vehicles meant for supporting purposes. The resultant impact was noticeable when the weaker Group B faced off stiff opposition in the Battle of Hannut in Belgium from 12th to 14th May. Accounts from the Panzer crews noted that their French counterparts operated in a “leaderless, aimless, badly commanded” manner.” Figure 2 displays the losses at this battle, with Germany seemingly on the losing end, but it has to be noted that the German Group B forces were facing the Allies’ main divisions and were never meant to be victorious. The significance of this battle was the need to occupy Allied forces while Group A proceeded to flank through the Ardennes which was largely possible due to the tactically organised divisions.

Apart from the Panzerwaffe, Blitzkrieg also employed the German Luftwaffe, with historians such as John Buckley considering it to be a defining component of the success of Blitzkrieg. Their role is evidenced by Hitler’s 11th directive where he mentions the Luftwaffe were to “prevent the transfer of enemy reinforcements to the front and to give direct support to our own forces”. This was done through strategic bombings, establishing air superiority and air support duties such as disrupting enemy back-lines. Buckley argues they played a major role in the in the early stages of the war from the 10th to 20th May as they began an intense air raid on the French fortifications with Stukas, Dorniers and Heinkels (Models of aircraft). They were never meant to be the main force of damage, but instead were pivotal in providing cover for the infantry’s crossing of the Meuse River just hours later. The speed and efficiency that the Luftwaffe provided ensured that the flanking of the Allied forces by Group A was possible by the 20th, cutting off the Allies’ best forces from retreat. Without the Luftwaffe, the invasion of the Low Countries would have been made a greater struggle, especially since the Germans had to deal with the Royal Air Force (RAF) intervening, thus displaying the Luftwaffe’s tactical importance in a German victory.

Despite this, Doughty argues that the success of the Luftwaffe is attributed to the French army’s ineffective air defenses. For instance, at Sedan, the French only had one battalion of anti-aircraft weapons, which had already placed them at a critical position. Furthermore, the capabilities of the French battalion were inconsequential, as exemplified on 13th May where only a singular German aircraft was shot down. This indicated that the Luftwaffe was not an extraordinary force but was only portrayed as such due to France’s unpreparedness to combat them. Additionally, while it is undeniable that the Germans did employ Blitzkrieg during the Battle of France, the tactic itself were considered to be ad hoc advances that required an overarching plan in order to be employed effectively. Thus, the tactics employed were made to seem more effective than they were in theory due to allied incompetence, with the strategy of Fall Gelb instead playing a more significant role in their victory.

Some historians offer an alternate perspective that the French invited defeat upon themselves in the Battle of France. This was due to a myriad of factors but mainly due to poor French military strategy and low national unity. The historians who support this argument include Ernest R. May, Robert A. Doughty and Joel Blatt, insinuating that the French’s various weaknesses were the leading cause for Germany’s victory rather than Germany's strengths.

Firstly, France’s primary weakness stemmed from their poor strategy, placing them at an easily exploitable position compared to their German counterparts. Their military philosophy was heavily centered on defence, particularly on the shared north-western border with Germany. This was due to the disastrous impact that World War I imposed on these regions, which were the economic hub of France. There was unanimous agreement for a line of defense along this area by France’s Generals, resulting in the inception of the Maginot Line constructed throughout the 1930s. However, the over-reliance of the line greatly contributed to France’s fall, as it failed to fulfill its usage, as it did not cover the Ardennes nor stretched to the coast, allowing the Germans to simply maneuver around it. Had they fortified the line in the Ardennes region, they would have greatly nullified the Germans as they would be unable to flank their elite forces stationed in Belgium, preventing the current variation of Fall Gelb from occurring. Both Gamelin and Petain believed that the Ardennes was difficult to maneuver and had the natural protection of the Meuse River, thereby not requiring fortification. However, this was a strategic blunder by the French since they were aware that the Germans had maneuvered through the Ardennes in previous wars such as World War I, so their belief that it was a natural barrier was not justified. In addition, Charles De Gaulle, commander of the French Fifth Army and later the president of the republic after World War II, had warned of an invasion through the Ardennes to his military superiors but was largely ignored.

Furthermore, French General Maurice Gamelin greatly contributed to France’s strategic failures. He was a renowned World War I general who rose through the French army’s ranks until he was appointed head of national defense in 1938. Despite his status as a respected and revered man, his lack of strategic competence and decision making ultimately played a significant role in the French defeat. For instance, he was responsible for the “Breda Variant” of the Dyle Plan, which was introduced in the beginning of 1940. This plan is outlined in Gamelin’s Instruction Personelle et Secrète no. 11, it included the reorganisation of the French 7th army to the front lines in Belgium, which weakened their reserves and its ability to defend the mainland since most of their forces were now positioned in the Low Countries. This was regarded as a strategic failure as France had acted against their previous plans where they had retained more reserve forces for counter attacking purposes, unlike what occurred here. Moreover, Gamelin had ignored advice from other officials such as General Georges who believed that they should not have committed all their forces forward as it left the French center vulnerable. As a result, it further compounded Germany's ability to encircle all their forces in Belgium as there were both weak and negligible reserves to fend off Group A from the Ardennes, and a greater proportion of their forces being lost earlier into the invasion.

Secondly, not only did France suffer from subpar military leadership, a lack of national unity was also a contributor to France’s downfall. Prior to the invasion, British Lieutenant-general Alan Brooke had described the French infantry to be ill-disciplined and insubordinate, leading to a damaging impact to overall morale. Moreover, France’s passivity towards Germany during the Phony War period led to soldiers being unoccupied with their duties, affecting military morale. The problem was that the low morale had affected them prior to the battle, which determined the indifferent nature that the soldiers had, resulting in an ineffective military. As a result, the German break at Sedan on 15th May was made easier, with Doughty arguing that this caused the French 55th division to panic and collapse in its defensive positioning. Doughty’s view on morale being a reason for the French defeat is also supported with Gamelin blaming the soldiers’ morale for the defeat at Sedan. While poor morale was certainly not the main cause of France’s fall, it undeniably exacerbated the myriad of other military problems that they were facing. Therefore, Doughty and May argue that the defeat of the French at the Battle of France was due primarily to France’s strategic incompetence and lack of national unity which caused the military morale to be compromised.

However, some French military personnel present during the battle claimed that during the Battle of Meuse, morale was one of their strengths which assisted them in halting German advances. The commander of one of the French tank units was quoted to mention that “The morale of the unit was splendid” during the German advance at Meuse, seemingly contradicting the notion that French morale was detrimental to themselves. Additionally, French General Weygand had also mentioned that French “morale is excellent” a year prior, suggesting that even before Germany’s invasion, France’s forces had not been negatively impacted by weak morale. This means that German victories such as the one at Meuse was due largely to the role of Blitzkrieg in overwhelming the French forces rather than the French military’s incompetence.

Despite this, Doughty’s perspective regarding French morale is valuable based on origin and content as his book utilized an accumulation of personal anecdotes by French forces that were collected directly after the confrontation at the Meuse as early as the 18th of May, indicating that the conclusion Doughty made was drawn from a variety of primary accounts. Further, his perspective is also valuable based on origin as his work was published in 1990 when he had access to the German archives that were not entirely obtainable prior to that year, allowing him to construct a complete narrative regarding the morale of the French soldiers. Nevertheless, Doughty’s book is limited based on content as it only showcases the factors behind Germany’s victory at Meuse. This is problematic as it does not consider other events during the Battle of France that demonstrates Germany’s strategic and tactical strengths or France’s weaknesses. It is also limited based on purpose as Doughty’s aim of the book was to portray the Battle of Sedan as the breaking point of the Battle of France, overstating French failures that occurred at this one battle as more significant than they were. Hence, Doughty’s argument for France’s weaknesses is not the most important cause for Germany’s victory at the Battle of France.

In conclusion, Germany’s victory at the Battle of France in 1940 can be attributed to their superior strategy in the form of Fall Gelb, the advantages that they had through the Blitzkrieg tactic, as well as the strategic failures and ineffectiveness of the French army caused by a lack of morale. This essay has discussed these factors and came to the judgement that the role of Fall Gelb was the most important in securing a German victory. This was due to the effectiveness of Blitzkrieg being partly exaggerated by weak French defenses which crumbled easily. In addition, Blitzkrieg is seen to be the means to carry out the strategy, but in itself is ultimately unable to be properly employed to ensure a German victory as Blitzkrieg’s effectiveness would have been diminished against a prepared French side which had not been encircled through Fall Gelb. At the same time, Gamelin’s role in the “Breda Variant” merely hastened Germany’s successes. Frieser argued that Germany would have overpowered the allies regardless if Gamelin had intervened, since Fall Gelb’s encirclement completely out-strategized France’s defenses. Therefore, Fall Gelb ultimately played a bigger role than the other factors in causing a German victory as it was both essential in giving a sense of direction for Blitzkrieg to succeed and was inherently superior to France’s strategy even without its mistakes.

Nevertheless, although this essay has discussed France’s weaknesses, it does not address other factors that contributed to France’s weaknesses. One such example was the growing internal disillusionment between the military and political sectors.

This was significant as the French government had also ignored warnings regarding Germany’s strategic plans leading up to May 1940 from military officials such as De Gaulle that could have prepared them for Germany’s invasion.

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