The breakthrough of Sedan is a major and decisive offensive during the Second World War, launched on May 10, 1940 by the Wehrmacht from Germany crossing Luxembourg and Belgium (Luxembourg Province) towards Sedan; German troops cross the Ardennes massif, deemed impassable by the French General Staff, and thus avoid the Maginot line, a line of fortifications extending from the Franco-Swiss border to the Franco-Belgian border. The main French and British armies were drawn to northern Belgium.
After overrunning the neutral states of Luxembourg and Belgium, while the other units controlled the ground and reduced pockets of resistance, General Heinz Guderian's 1st, 2nd and 10th Panzer Division moved towards Sedan. Of 7 armored divisions, 3 are in the Sedan sector. The attack plan focuses on an area of 5 km as the crow flies (10 km following the course of the Meuse) between the villages of Donchery and Wadelincourt located on either side of the town of Sedan.
On the French side, the region was defended by the 2nd Army (sector of Longuyon to the vicinity of Donchery) commanded by General Charles Huntziger and the 9th Army (sector of Donchery to Dinant in Belgium) of General André Georges Corap protecting the junction between the Maginot line and the Belgian border. The German attack is concentrated at the junction of these two armies, which are essentially made up of infantry units of low military value. In the rear, in the region of Châlons-sur-Marne, three French armored divisions were in reserve.
First fruits of the breakthrough
On May 10, while all attention is monopolized by the fighting in central Belgium, large German armored divisions, accompanied by infantrymen of great military value, cross Luxembourg and eastern Belgium. Despite the strategy of the French General Staff, this pivotal sector between the Maginot Line and the border is very poorly defended by troops with a combat value inferior to the French Armies deployed in Belgium and above all much less equipped with modern equipment, in particular from D.C.A. The strategy is guided by an erroneous doctrine of the French general staff who consider that the Ardennes massif is impassable by armored vehicles, but those of the Germans will cross it in two days.
On May 12, the French high command realized that the main attack was directed at Sedan and not towards northern Belgium as in August 1914 (Schlieffen plan). This battle plan called Fall Gelb (yellow plan) is the result of a joint reflection between Hitler and General von Manstein. The plan also says "sickle blow" plans to deceive the French general staff by simulating an attack by the Netherlands and Belgium. This plan is at the origin of one of the greatest military disasters of France.
The opposing forces
The Sedan sector is protected by the 55th division, which is mainly made up of 2nd reserve infantry troops. On May 10, an order from General Huntziger upsets the defense system by having units replaced in a sector that were familiar with the terrain. The total set-up of the units will end only on May 12. On May 14, at the height of the fighting, Huntzinger moved his command post. Along the Meuse, fortified works, casemates, forts all in reinforced concrete (many are still visible today following the course of the Meuse) were built from 1938 and during the phoney war. But many of these works are not finished and when they are, few are fully equipped. Some do not even have armored doors, others have unsuitable guns or even lack grenade launchers... The lines of defense lack depth and coherence, the banks of the Meuse are not protected by wires barbed wire, the trenches are not connected to each other. The infantry are supported by artillery (75, 105 and 155 mm guns) and are in a sector south of Sedan between the villages of Frénois and Bulson in the Marfée forest (already the site of a battle in Model:17th century). This forest is located on a plateau overlooking Sedan and the Meuse. Transmissions are by buried telephone lines and not by radio.
Opposite, German troops of high military value, very seasoned and trained, are concentrating on three sectors between Donchery and Wadelincourt. From the von Kleist armored group, 3 panzerdivisions with their infantry are in the Sedan sector:the 1st armored division west of Sedan between Glaire and Torcy, the 2nd at Donchery, the 10th at Wadelincourt.
The fights
* The German advance guards are very close to the border (8 km from Sedan) when all the bridges in the Sedan sector are destroyed on May 12 at the end of the afternoon. The French army awaits the German assault on the left bank of the Meuse.
* On May 13 at dawn, French observers saw numerous German columns appearing at the edge of the forests north of Sedan. The French artillery fired effectively, hampering the progress of the German troops. Hundreds of bombers (Dornier, Heinkel and Junker) stalk the French sector. These bombers are protected from French and English air fighters by Messerschmitt Bf 109s. The Ju 87 stukas with their howling sirens add a demoralizing and distressing effect for the defenders. The "too few" French anti-aircraft artillery also failed to clear the sky. The German tanks and self-propelled guns arrived on the banks of the Meuse begin to fire.
* Around 4 p.m., the shelling ceased. Under the cover of smoke shells, German assault infantrymen cross the river on board rafts, inflatable boats in the three predefined sectors. After having suffered the bombardments, the French defense lines are completely disorganized, the German infantry quickly reach the casemates, forts and trenches which they bypass if they resist too much. Many French defenders are haggard and stunned, some casemates defend themselves heroically but lack support because many telephone connections are cut and artillery fire, for lack of precise information, is ineffective. Rockets requesting artillery support are misinterpreted or overlooked, and the batteries also had to reorganize after the bombings. The confusion is almost general on the French side, many units break up and many soldiers are taken prisoner.
* At the start of the evening, all the defensive works between Donchery and Wadelincourt fell. The Germans established a solid bridgehead on the left bank of the Meuse in less than a day. During the night the German pioneers can build pontoon bridges over the Meuse to allow the passage of armored vehicles. A first floating bridge was built west of Sedan, near the village of Floing, at a place called "Gaulier" in the courtyard of the Espérance factory. However, on the evening of May 13, no German tank had yet crossed the Meuse.
* On May 14, Guderian's tanks are on the left bank of the Meuse, the French device at the junction of the Corap and Huntziger armies is pressed despite the attempts of many French and British planes to destroy the bridges. The flak is very effective, reinforced by the luftwaffe. The French have regrouped towards the village of Chéhéry, Guderian immediately sends his panzers towards this place. A movement of panic has affected the French troops who are not withdrawn in order, so much so that many heavy artillery batteries will not be destroyed and the CPs evacuated.
Attempted counterattack
From May 15 to 18, a French counterattack was attempted south of Sedan in the Stonne, Raucourt, Sy sector by B1 heavy tanks and French infantry, including many colonial troops. But the tanks of the 3rd DCR used in small packages are overwhelmed by the number of German panzers. Guderian's tanks find two intact bridges over the Ardennes Canal, near Omicourt and Malmy. Guderian's strategy of using tanks en masse, protected by strong air support, works wonders. Colonel Charles de Gaulle also recommended it a few years earlier, but the French general staff did not believe in his doctrine. On the other hand Guderian and Rommel retained it and put it into practice. This strategy will later be theorized under the term blitzkrieg (lightning war) and was put into practice during the invasion of Poland in September 1939, at the start of the conflict. The French general staff learned no lesson from this conflict during the phoney war, no questioning of the doctrine for the use of tanks.
Consequences of the Sedan breakthrough
General Corap, further north, no longer having a connection to Sedan, overwhelmed in the north and threatened in the center, ordered a hasty withdrawal to the French border which was to strip the 1st Army which was resisting in Belgium and forced it to abandon its positions. on the gap of Gembloux on May 15 to fall back on the left bank of the Scheldt.
Despite French and British resistance, the Germans reached the sea at Abbeville on May 21, encircling the French, British, and Belgian armies in northern France and Belgium. The Falb Geld (yellow plan) has worked, the best allied units, cut off from their staff, are trapped in a huge pocket.
On May 17, a counter-attack limited to Montcornet was launched by the 4th reserve armored division commanded by Colonel Charles de Gaulle, however this localized success, repeated later near Abbeville, was not enough to thwart the plans. Germans.
* May 19, the French Generalissimo Gamelin is dismissed and replaced by General Weygand. This takes up Gamelin's combat plan after which recommended that the northern army group go back down to the south. But the armies fell back to Dunkirk, where the British organized the re-embarkation of their expeditionary force during Operation Dynano. Then, the Germans will break into France, shaking up the line of defense put in place by Weygand which goes from the mouth of the Somme to Vouziers in the Ardennes.
The errors of the French command
* The German breakthrough, known as the "Sedan breakthrough", was in fact carried out on a front that goes from Sedan in the south to Dinant in the north, with Dinant and Monthermé as the main crossing points. This rapid advance is explained by the strategic error of the French general staff (Generals Gamelin and Georges), to advance its best troops in Belgium and the Netherlands to the supposed meeting of the bulk of the German forces, while the he essential of the German offensive is concentrated on the weakest point of the French system, much further south, in the sector of the Ardennes, held by weak infantry troops who will face the best German units concentrated on this point forehead gravity. Allied aerial reconnaissance had nevertheless spotted the movements of the German units as early as May 10.
* The surprise of the breakthrough at Sedan, the lack of rapid reaction and the dispersed use of French armored divisions poorly supported by aviation during the counterattacks, explain why the effects of the initial strategic fault could not be corrected and the “closed” breach. The doctrine of the French general staff was based on the defensive and no lesson had been learned from the start of the conflict in Poland in September 1939. For several months, the belligerents watched each other at gunpoint, allowing the Germans to replenish their various stocks. However, the French also took advantage of this period to complete their armament and constitute a few armored divisions. This period, called the "phoney war", will abruptly end on May 10, 1940. Some historians believe that France was more prepared for a long war, the manpower was balanced and of equal value, the materials were of equivalent value . But misused against the Germans who exploited the ruse of the yellow plan to perfection, the French armies suffered one of the greatest defeats in their history. The French human losses will be considerable because in just over a month of effective war more than 90,000 combatants will be killed or missing.
* Almost 70 years earlier, Sedan had previously been the scene of decisive military operations for the Germans. Indeed, during the Battle of Sedan from August 31 to September 1, 1870, a coalition of German states had routed the French army, precipitating the fall of the Second Empire and the advent of the Third Republic. On May 13, 1940, although the front was more extensive, the main effort of the German army was concentrated on the Sedan sector. This battle was also decisive and went down in history as the breakthrough of Sedan. The city of Sedan will once again be at the origin of the agony of a political regime which will be de facto abolished on July 10, 1940 by the National Assembly (Chamber of Deputies and Senate combined) which gave full powers to the Marshal Petain. The latter asked for an armistice which was signed on June 22, 1940 in Rethondes and gave birth to the Vichy regime.