It was part of the German Wehrmacht's operational plan codenamed Fall Gelb (Case Yellow) for an offensive through the hilly and forested Ardennes, to encircle the Allied armies in Belgium and north-eastern France.

Crossing the Meuse had enabled the Germans to achieve the operational goal of Fall Gelb and encircle the strongest Allied armies, including the British Expeditionary Force.

The resulting June battles destroyed the remaining French army as an effective fighting force and expelled the British from the continent, leading to the defeat of France.

Once these lightly defended areas were negotiated, Army Group A's XIX Panzerkorps (19th Tank Corps), under the command of Heinz Guderian, was to strike into France at Sedan, located on the Meuse river.

[23] The French Army authorised fresh attempts to increase the strength of the fortifications in the autumn of 1939, but severe winter weather prevented the pouring of concrete and the delivery of the necessary materials.

The steep slopes on the banks of the Meuse, added to what appeared in photographic reconnaissance to be a formidable barrier of bunkers and defence lines, caused Colonel-General Gerd von Rundstedt, the commander in chief of Army Group A, to question the wisdom of Guderian in choosing Sedan as the point of maximum effort.

[26] To the north of Sedan, on the northern bend of the Meuse, the town of Glaire overlooked the crossing points on the river, which was to be where the German armour would deliver its heaviest blow.

[28] As the German Army advanced through southern Belgium on 12 May, General Ewald von Kleist and Guderian clashed over where the main point of effort should fall.

Guderian saw things differently, and pointed out that a thrust along the lines of Kleist's plan would put the flank of the advance within range of the fortress artillery at Charleville-Mézières, some 25 kilometres (16 mi) north west of Sedan.

The shift of operations further north would also disperse concentration (or Schwerpunkt) and disrupt the intense planning of the German tactical units, who had been in training for the Sedan attack and an advance north-west, for months.

[8] In total Guderian could possess 3 out of 8 divisions that Panzer Group Kleist had, gathering a force of up to 60,000 infantry troops, 41,000 vehicles, 788 tanks and 141 artillery pieces.

Fliegerkorps, nicknamed the Nahkampf-Fliegerkorps (Close Support Air Corps), which contained Sturzkampfgeschwader 77 (Dive bomber Wing 77), a powerful concentration of dive-bomber units equipped with the Junkers Ju 87 Stuka precision ground attack aircraft.

One officer, First Lieutenant Delas of the 1st Battalion 147th Fortress Infantry Regiment was arrested and confined for 15 days for ordering firing practice with a 25mm anti-tank gun in a nearby quarry.

[43] In the early hours of 13 May, the 10th Panzer Division slipped into position upstream to the north-east of Sedan, ready to strike at its designated crossing point near the town of Wadelincourt.

To restrict enemy movements and communications, German fighters swept the area to cut land-lines and strafe fortifications, with some shooting of radio antennae off command posts.

Crossing at the extreme western end of the Sedan sector on the Donchery axis, it was forced to advance across open terrain for the last 3 km before reaching the bridgehead.

Unsupported and acting on their own initiative, this small force led by Feldwebel Walter Rubarth opened a decisive breach by knocking out seven bunker positions.

General Gaston-Henri Billotte, commander of the First French Army Group, whose right flank pivoted on Sedan, urged that the bridges across the Meuse be destroyed by air attack, convinced that "over them will pass either victory or defeat!".

[71] During 14 May, General Lafontaine had moved the 55th Infantry Division's command post from its position on the Marfee heights to Bulson, 10–11 kilometres (6–7 mi) south of Sedan.

The terrain included heavily wooded areas, and the units left behind convinced General Charles Huntziger, commander of the French Second Army, that they would be able to hold Bulson, and the Germans would not be able to exploit their tactical victory at Sedan on 14 May.

The French had already initiated plans for counter-attacks with armour on the German-held bridgehead during the night but delays in bringing up forces and hesitation on the part of local overall French command at large, made worse by mistaken intelligence reports and by the resulting confusion from the panic and retreat of the infantry who had also abandoned their positions and artillery as part of the "panic of Bulson",[73] made an attack possible only in the morning of 14 May.

However, the French commanders, deeply schooled and versed in the defensively-focused doctrine of methodological warfare, were located far to the rear, which meant they lacked a real-time picture of the battle.

This was to prove fatal, especially coupled with the fact that the French generalship at large was expecting a considerably more prolonged process of initial German assault phase and overall attack effort as a whole.

He spent hours reconnoitring the terrain, sometimes trying to contain and reason with fleeing, routing scores of French infantrymen and artillerymen of the 55th and 71st Infantry Divisions, and travelling around the area to various regimental headquarters, looking for his Corps commander, General Gransard (who was deliberately reconnoitring the terrain, for some time, at that relative point in time), for an order to attack, and, in the meantime, extemporarily assessing and conferring with some local command personnel.

Owing to this, Lafontaine also delayed issuing orders to the tactical attack units until 05:00 on 14 May, by which time the Germans had consolidated their bridgehead and the Panzer divisions' combined arms infantry teams were already advancing inland to Bulson.

[76] The French had an opportunity to throw the Germans back into the Meuse but they missed their chance owing to poor staff-work, compounded by confusion, hesitation, delays in bringing up forces, mistaken intelligence reports, and lack of quick response.

The 37 mm guns struggled to halt the French armour which then outflanked the position at Connage by moving to the west while the infantry advanced from the south east on the German right flank.

[75] Delays on the right flank meant the 205th Infantry Regiment and 4th Tank Battalion did not reach their starting line until 10:45, by which time the battle on the left wing had been lost and further attacks on the right would have made little sense.

General Franz Halder had dropped this from Fall Gelb, but Guderian resurrected it and ordered the 10th Panzer Division and Großdeutschland Infantry Regiment to attack across the Stonne plateau.

The limited and relatively meager Allied flank protection that there existed was swiftly, rapidly, and handily defeated by the German forces in their driving and pressing offensive attack-thrust from their breakout at Sedan.