Under the command of Generaloberst Gerd von Rundstedt, and with key commanders such as Heinz Guderian and Erwin Rommel, Army Group A deployed 45½ divisions, including seven Panzer divisions, to execute a rapid and overwhelming assault.

The plan, based on speed, surprise, and coordination, aimed to bypass the heavily fortified Maginot Line and strike at the heart of France from an unexpected direction.

By breaching the Meuse River and driving swiftly to the English Channel, Army Group A played a critical role in encircling and defeating the Allied armies.

General Heinz Guderian, commander of XIX Panzer Corps, was the driving force behind the armored thrust through the Ardennes.

A pioneer of Blitzkrieg tactics, Guderian had extensively studied and promoted mechanized warfare in the 1930s.

His leadership at Sedan, where his tanks rapidly crossed the Meuse River and shattered French defences, was instrumental in the success of Army Group A.

Guderian’s emphasis on speed, independent command, and radio communication allowed German Panzer forces to outmaneuver and encircle Allied forces effectively.

• 1st Panzer Division: Commanded by Generalmajor Friedrich Kirchner, this division was well-equipped with Panzer III and IV tanks and played a key role in the initial attacks.
• 2nd Panzer Division: Under Generalmajor Rudolf Veiel, it contributed to the rapid advance towards the Meuse River.
• 10th Panzer Division: Led by Generalmajor Ferdinand Schaal, it provided additional firepower and mobility for Guderian’s rapid assaults.
• 7th Panzer Division (Erwin Rommel): Nicknamed the "Ghost Division", the 7th Panzer Division was commanded by General Erwin Rommel and became famous for its aggressive and unpredictable movements. Equipped with Panzer 38(t) tanks, it played a major role in the encirclement of Allied forces, advancing further and faster than expected.

While much of the logistics train was still reliant on traditional methods, the Panzer divisions were supported by motorized supply columns, bridging engineers, and repair battalions to keep tanks operational. Units like the Kraftfahrtruppen (motor transport troops) ensured fuel and ammunition reached the front lines.

Army Group A’s divisions were equipped with 105mm leFH 18 howitzers for infantry support and 150mm sFH 18 heavy howitzers for long-range bombardment.

The 88mm FlaK 36, initially an anti-aircraft gun, proved invaluable as an anti-tank weapon, devastating French armour.

The Sanitätsdienst (medical service) included field hospitals, mobile surgical units, and medical transport, ensuring rapid treatment of wounded soldiers to sustain the offensive’s momentum.

VIII Corps, commanded by General of Infantry Walter Heitz, provided essential infantry support to Army Group A, securing key positions, maintaining supply lines, and reinforcing breakthroughs made by Panzer divisions.

This corps included the 8th Infantry Division, led by Generalmajor Rudolf Koch-Erpach; the 28th Infantry Division, initially under Generalleutnant Hans von Obstfelder before Generalmajor Johann Sinnhuber took over on May 20, 1940; the 87th Infantry Division, commanded by Generalmajor Bogislav von Studnitz; and the 267th Infantry Division, led by Generalmajor Ernst Fessmann.

Generalleutnant Eberhard von Mackensen served as his Chief of Staff, overseeing a well-structured and highly disciplined force composed of multiple corps and divisions.

III Corps, under General of Artillery Curt Haase, included some of the Wehrmacht’s most experienced infantry units: the 3rd Infantry Division, led by Generalleutnant Walter Lichel; the 23rd Infantry Division, commanded by Generalleutnant Walter von Brockdorff-Ahlefeldt; and the 52nd Infantry Division, under Generalleutnant Hans-Jürgen von Arnim.

VI Corps, led by General of Engineers Otto-Wilhelm Förster, brought strategic versatility with the 16th Infantry Division under Generalmajor Heinrich Krampf and the 24th Infantry Division, initially commanded by Generalmajor Justin von Obernitz before Generalmajor Hans-Valentin Hube took over on June 1, 1940.

With Generalmajor Walter Model acting as Chief of Staff, this meticulously structured force played a pivotal role in Germany’s invasion of France.

Comprising multiple corps, each under the command of seasoned officers, the army was positioned for swift, decisive action.

General of Infantry Eugen von Schobert led VII Corps, which included the 36th Infantry Division under Generalleutnant Georg Lindemann and the 68th Infantry Division led by Generalmajor Georg Braun.

These infantry units provided a strong foundation for the German advance, ensuring territorial gains were consolidated as the offensive progressed.

At the heart of the German strategy was Panzer Group Kleist, commanded by General of Cavalry Paul Ludwig Ewald von Kleist, with Generalmajor Kurt Zeitzler as his Chief of Staff.

This powerful armored force was responsible for delivering the devastating thrusts of Blitzkrieg, utilizing speed, firepower, and coordination to overwhelm enemy defenses.

XIV Corps, led by General of Infantry Gustav Anton von Wietersheim, spearheaded the motorized assault with the highly mobile 2nd Infantry Division (motorized) under Generalleutnant Paul Bader, the 13th Infantry Division (motorized) commanded by Generalmajor Friedrich-Wilhelm von Rothkirch und Panthen, and the 29th Infantry Division (motorized) under Generalmajor Willibald Freiherr von Langermann und Erlencamp.

These fast-moving divisions were instrumental in outpacing Allied forces and creating gaps in their defensive lines.

Strategic reserves were held under XXXX Corps, commanded by Generalleutnant Georg Stumme.

This crucial reinforcement force included the 6th Infantry Division under Generalleutnant Arnold Freiherr von Biegeleben, the 9th Infantry Division led by Generalleutnant Georg von Apell, the 4th Infantry Division under Generalleutnant Erick-Oskar Hansen, the 27th Infantry Division commanded by Generalleutnant Friedrich Bergmann, the 71st Infantry Division under Generalleutnant Karl Weisenberger, and the 73rd Infantry Division led by Generalleutnant Bruno Bieler.

These reserve units ensured that fresh troops could be deployed at critical moments, sustaining the momentum of the German offensive.

• Messerschmitt Bf 109 – The primary fighter aircraft, escorting bombers and engaging Allied aircraft to maintain air superiority.
• Junkers Ju 87 Stuka – The infamous dive bomber was used for precision strikes on French fortifications, bridges, and troop concentrations. Stukas played a key role in breaking French defenses at Sedan, where they relentlessly bombed French positions to clear the way for Heinz Guderian’s Panzer divisions.
• Heinkel He 111 and Dornier Do 17 – Medium bombers used for strategic and tactical bombing, hitting supply lines and communication hubs.
• Henschel Hs 126 – A reconnaissance aircraft providing real-time intelligence on enemy troop movements to German commanders.

By 1940, this assumption became a critical weakness in Allied planning.

The French military, heavily influenced by the First World War experiences, focused its defenses on the heavily fortified Maginot Line to the east and expected the main German assault to come through Belgium, as it had in 1914.

The Ardennes was left lightly defended, as French military doctrine deemed it impassable for large armored forces.

Only second-rate divisions, consisting mostly of reservists and under-equipped troops, were stationed there.

The key battle took place at Sedan on the 13th May 1940, where Guderian’s Panzer Corps led a crossing of the Meuse River.

The Germans unleashed a massive artillery and Luftwaffe bombardment, particularly using Stuka dive bombers (Ju 87s) to demoralize and weaken French defences.

This relentless air-ground coordination shattered the French 55th Infantry Division, allowing German assault pioneers and Panzergrenadiers to force a crossing.

The French counterattacked with De Gaulle’s 4th Armored Division, but their efforts were disorganized and repelled by 88mm anti-aircraft guns repurposed as anti-tank weapons.

By the 15th of May, German forces had completely secured the area, opening a path for a deep armored thrust.

Following the breakthrough at Sedan, Army Group A launched its "Sickle Cut" (Sichelschnitt) maneuver, sweeping westward toward the English Channel.

Guderian, Rommel, and Hoth’s Panzers raced ahead of the slower-moving infantry, ignoring direct orders to slow down in favor of maintaining momentum.

It was during these actions that the 7th Panzer Division under Rommel gained fame due to its rapid, unpredictable movements, striking deep into French rear positions and capturing key cities like Cambrai and Arras by May 20.

By June 5, Army Group A resumed its advance in Fall Rot (Case Red), pushing south into central France.

German forces rapidly seized cities like Reims, Troyes, and Châlons-sur-Marne, with Paris falling on June 14.

Army Group A’s relentless Blitzkrieg tactics, superior coordination, and overwhelming speed ultimately ensured the swift collapse of French resistance, leading to the armistice on the 22nd June 1940.

With France defeated, Army Group A's immediate role shifted from offensive operations to consolidation and garrison duties.

Its forces were stationed in northern and western France, maintaining order and securing key locations.

Additionally, elements of the army group were tasked with planning and preparations for Operation Sea Lion, the proposed German invasion of Britain.

However, as the Luftwaffe failed to achieve air superiority in the Battle of Britain, the invasion was postponed and ultimately abandoned.

By 1942, it was heavily involved in the Caucasus offensive, seeking control of vital oil fields.

However, strategic overextension and the Soviet counteroffensive turned the tide.

Ultimately, Army Group A’s role in the aftermath of the Battle of France was pivotal in securing German control over Western Europe but also marked the beginning of its transition to more challenging and prolonged conflicts on the Eastern Front.

The breakthrough in the Ardennes, characterized by rapid movement through difficult terrain, was central to this success.

The unexpected advance through the Ardennes caught the Allies off guard, enabling German forces to swiftly cross the Meuse River.

The use of artillery and air strikes effectively shattered defensive positions, creating openings for an armored push into the heart of enemy territory.

Despite Allied attempts to mount counterattacks, German forces swiftly adapted, leveraging superior mobility and coordination to maintain the initiative and prevent the opposition from regrouping.