December 21, 1940, Saturday, clear skies.
The rising sun cast its orange light upon the earth. After a whole night of turmoil, from the top of Sinfjord in the Bristol Bay to Reading, just over 60 kilometers from the center of London, the 106-kilometer-long British defensive line was in ruins. From the air, the myriad craters turned the field fortifications, constructed over two months by millions of British civilians and soldiers, into a lunar landscape. The mushroom-shaped fortresses, struck directly by shells, resembled crushed eggs, a testament to the tremendous power of the enemy's artillery barrage!
Since early November, the Germans had transferred two K5E-type railway guns deployed on the Isle of Wight to Portsmouth and brought in another three heavy railway guns with calibers exceeding 200 millimeters from mainland Germany. Coupled with the formidable artillery corps of the German Army, over a thousand guns roared intermittently for nearly 12 hours. Rumors about insufficient German transport capacity and shortages in supplies for the landing forces were shattered by reality!
In the German front lines in Reading, the infantry of the 16th Infantry Division of the German Wehrmacht had entered the departure positions along the communication trenches. Officers used simple trench periscopes to carefully observe the situation across the way. The British positions were as quiet as a giant graveyard; some burning materials ignited by artillery fire were still emitting dark smoke.
"Soldiers of the 2nd Company, remember, our target is the outermost section of the British trench directly ahead. When we attack, our allies will send tanks to support us. Once we capture the position, don't rush to advance deeper. Instead, thoroughly clear out those trenches and anti-aircraft shelters, eliminate the British soldiers inside, and remove any suspicious explosive devices. We will hold that position until the arrival of the anti-tank artillery detachment! Is that clear?"
In the trench, a German captain of average build with bright eyes reminded the soldiers who were preparing their equipment. Nearly 200 soldiers were squeezed into a short section of trench in two rows. In addition to the most common Mauser 98K, MP38, and MG34, every twenty soldiers were equipped with one or two "Panzerschreck" anti-tank rocket launchers in the shape of a cudgel. Since their large-scale deployment, German officers realized that this weapon, originally intended to enhance defense, had a range and power comparable to hand grenades (only veterans could throw the STG39 long-handled grenades 50 meters or even farther when standing), making it effective in offensive operations as well. After practical tests in several battles in southwest England, the German Army Headquarters finally equipped the "Panzerschreck" to infantry squads at the grassroots level in early November. In the German infantry divisions landing in Britain, each company had several "Panzerschreck" anti-tank combat teams, and motorized infantry companies had specialized "Panzerschreck" anti-tank combat squads. In terms of combat effectiveness, calling them "demolition assault groups" might be more appropriate.
A familiar buzzing sound came from behind the defensive lines. Some veterans were even too lazy to turn their heads to see the spectacular sight they had become accustomed to: a swarm of Stuka dive bombers flew past, with each formation consisting of three or six aircraft. They attacked ground targets with 250-kilogram and 50-kilogram high-explosive bombs. Of course, the sound emitters mounted under the aircraft's nose were among the best psychological suppression equipment of the era!
Except for the "black cotton candy" created by the British ground-based anti-aircraft fire, the azure sky was filled with German combat aircraft painted with blue-green block camouflage. Although the Luftwaffe's cessation of bombing raids on northern England had alleviated the pressure on British aircraft production lines, due to the increasing number of airfields around Cardiff, the German Air Force had deployed an entire squadron of BF-109 fighters to the northern main battlefield. In the numerous aerial dogfights over the past week, the flexibility and striking tactics of the German fighter units had shown obvious superiority—an unexpected development for the British high command. The death of Reich Marshal and Commander-in-Chief of the Luftwaffe Hermann Göring not only failed to affect the morale of the German Air Force but also liberated the technical advantage of German pilots in terms of strategy and tactics.
The sharp whistling filled the ears, and the intense explosions shook the earth. The surging shockwaves rolled over the open battlefield, allowing the officers and soldiers in the German trenches to feel the warmth firsthand.
In view, the British front line, already riddled with holes, had suffered further devastation from the mass bombardment of "aerial assault artillery." However, the ordeal was far from over. After half an hour of respite, the German artillery in the rear suddenly launched a rapid barrage that lasted for ten minutes. This tactic was tailored to exploit the characteristic traits of traditional defensive warfare—if the British commanders ordered their troops to urgently enter defensive positions at this moment, they would suffer significant losses from the German follow-up bombardment!
After the ten-minute bombardment, German officers in the trenches loudly reminded the soldiers of the first wave of attackers to prepare themselves. At the same time, the rumble of engines emanated from the positions behind the departure lines. Unlike the aircraft from above, these sounds were accompanied by the creaking of metal friction, and the smell of poorly burnt gasoline permeated the air. As armored vehicles crossed the trenches and raced towards the British positions, the officers' whistles finally sounded in the ears of the soldiers.
"Attack!"
On the extensive battlefield, tens of thousands of German infantry climbed out of the trenches with ladders. They possessed the same determination for victory as the German army in 1914, but with notable differences. The ornate spike helmets were replaced by the iconic M36 steel helmets, the heavy backpacks were nowhere to be seen, replaced instead by ammunition pouches and gas masks more suitable for field combat. The sharp bayonets still hung at the waists of the riflemen, while submachine gunners inserted wooden handle grenades into their belts or boots. Officers continuously waved their Luger 08 or Walther 38 pistols, urging their soldiers to charge alongside tanks and armored vehicles!
In terms of tactics, the British defense had fully utilized the combat power of their existing personnel and equipment; strategically, it was the desperate struggle of a doomed group for survival. With the extensive use of defensive weapons made from gasoline or unrefined petroleum by the British defenders, the long frontlines had turned into a sea of flames. However, this still could not stop the German assault tactics.
When the flames subsided slightly, German tanks, assault guns, and armored vehicles rushed up to the positions with overwhelming momentum. Large numbers of German infantry, wearing gas masks, quickly followed suit, and the rattling of MP38s began to fill the British trenches. In some areas, brutal hand-to-hand combat erupted. The final outcome ended with the swift breakthrough of the German frontline trenches, where the advantage in numbers, morale, and equipment almost overwhelmingly favored the German forces. However, the German forces on the eastern side of the front line did not immediately advance towards the British depth positions; instead, they stabilized their positions and organized defenses on the spot. The British doubts were soon answered:
On the western side of the front line, the Germans formed an invincible armored cluster with the 2nd, 4th, 5th, and 9th Panzer Divisions of the Wehrmacht, supported by uninterrupted aerial suppression from the 8th Air Corps. Within just four hours, they ruthlessly pierced through three layers of British defenses in depth. Eight elite Wehrmacht infantry divisions surged forward, expanding the breakthrough, originally only four kilometers wide, to fifteen kilometers. The main force of the powerful armored cluster split into two. The left wing encircled the north of Sinfjord. By 4 p.m., they successfully merged with the German forces attacking from Cardiff, effectively enveloping tens of thousands of British regular troops and over ten thousand second-line militia at the northern end of the Sinfjord-London defense line. The right wing bypassed northwest London and rushed towards Wash Bay, trapping the British and their comforting Greater London defense circle in a situation of being surrounded on all sides.