The Great Allied Tank Offensive of 1917
Prologue: The Battle of Paardeberg, South Africa, February 1900
Major General Horace Smith-Dorrien could not believe what he was seeing. Throughout the scorching South African summer day the British infantry had been ordered into reckless frontal assaults against an entrenched Boer position. The task had been hopeless. The famous Afrikaner marksmen had gunned down the attackers time and again. The dusty veld was carpeted with khaki-clad bodies that revealed the futility of the British tactics. But now, yet another attack was being formed up in the early evening light.
Watching through binoculars, Smith-Dorrien looked on in dismay as the British line rose from cover with a roar and moved forward at the double. A crash of rifle fire burst from the Boer line in response. Officers leading the advance with swords drawn were prime targets and were swiftly picked off. The British line convulsed as bullets ripped through its ranks. Gaps appeared. Survivors bunched together, pushing forward, stepping over the fallen of earlier assaults. The Boers concentrated fire on these heroic pockets and mowed them down. Within minutes it was all over. The attack had simply been destroyed.
The attack left a deep impression on Smith-Dorrien. He remembered after the war: ‘It was a gallant charge, gallantly led, but the fact that not one of them got within 300 yards of the enemy is sufficient proof of its futility.’ No amount of heroism could overcome the effects of modern firepower. Surely there had to be a better way of making war?
The desire for a ‘better way’ would plant a seed in Smith-Dorrien’s mind that would finally bear fruit in the First World War – but first, the solution had to be devised.
Necessity is the Mother of All Invention
In December 1903 the visionary science fiction author H. G. Wells published his story ‘The Land Ironclads’ in the Strand magazine. The prescient tale took place during a thinly disguised reimagining of the Boer War, where an army representing the British became deadlocked by the trenches of their opponents. After a month of stalemate, a bold new weapon takes to the field – the land ironclads of the title, mechanical behemoths one hundred feet in length, studded with guns and guided by huge searchlights. The mechanical monsters prove invulnerable to the rifle fire of the enemy and crush the defences with ease. In years to come, Wells would look back with pride on his prediction of armoured warfare.
Unfortunately for the British Army, the technology described in the story still lay in the future. Working with the equipment that was available, a number of officers proposed the use of bulletproof, man-portable shields that could be carried or rolled across the ground. Numerous experiments took place in Britain and India. Disappointingly, all work with the shields proved unsatisfactory. The devices were heavy and unwieldy, and it was soon found that they were only mobile on firm, flat ground.
However, an unorthodox and intriguing design emerged in 1912. After several uncomfortable experiences driving trucks over rough terrain, Australian inventor Lancelot de Mole designed a caterpillar-tracked transporter that could carry heavy loads across battlefields. Although he envisaged a transport rather than a fighting vehicle, de Mole suggested that his machine would be capable of crossing trenches and sufficiently armoured to withstand enemy fire. De Mole forwarded his proposal to the British War Office. In a stroke of good fortune, the design was brought to the attention of General Sir Ian Hamilton. Earlier in his career Hamilton had favoured the use of super heavy artillery and had been intrigued by the idea of using steam traction engines to haul it into battle. Hamilton used his influence to attract interest in de Mole’s design, prompting the Royal Engineers to carry out a feasibility study on the vehicle. The resulting report was issued in early 1914 and drew a very favourable conclusion. Unfortunately, the scandal of the Curragh incident7 in March and command reshuffle that followed distracted the authorities and the report was largely forgotten.
The outbreak of war in August 1914 came with armoured technology still beyond reach. Instead, the British Expeditionary Force marched into battle relying on suppressing fire, use of cover, and extended formations to keep its infantry safe. These methods served well enough in the defensive battles of August 1914. But the casualties suffered attempting to storm the German trenches at the Battle of the Aisne in September gave a stark warning that the killing power of modern weapons now far exceeded those that had been used in the Boer War. Defenders occupying earthworks could inflict severe losses on any attacker whilst suffering comparatively few in return. This imbalance between attack and defence led to the trench deadlock that took hold of the Western Front at the end of 1914. The lines ran from the Channel coast to the Swiss border. There were no flanks to turn, no room for manoeuvre, and seemingly no way through the barbed wire, machine guns, and artillery fire of the defenders.
The British Army cast about for solutions to the impasse. Amongst the many officers drawing up proposals was the official war correspondent Ernest Swinton. An intelligent and imaginative man, Swinton remembered a conversation with a friend who had once suggested that civilian tractors running on caterpillar tracks might have some military application.8 In October, Swinton had passed his thoughts on to his friend Colonel Maurice Hankey, who was working as an assistant to the prime minister.
On 28 December 1914, Hankey issued a paper of military ideas known as the ‘Boxing Day Memorandum’. Amongst various suggestions for the conduct of the war there was a paragraph that spoke of the future. Hankey suggested the use of ‘Numbers of large heavy rollers, themselves bullet proof, propelled from behind by motor-engines, geared very low, the driving wheel fitted with a caterpillar driving gear to grip the ground, the driver’s seat armoured and a Maxim gun fitted. The object of this device would be to roll down the barbed wire by sheer weight, to give some cover to men creeping up behind and to support the advance with machine gun fire.’
This paragraph had an electrifying effect on Winston Churchill, then serving as First Lord of the Admiralty, who immediately wrote to the prime minister urging that the proposal be pursued.10 The vehicle that would ultimately become known as the tank had a powerful supporter. Science fiction was about to become reality.
Armoured cars had served with some success in 1914 but the idea of creating a tracked fighting vehicle was a new concept within the British military. It was such a radical idea that it was not clear who should have authority over the design. Should it be developed by the navy, which had more experience with steel and engines, or by the army, who would actually use it in battle? Without a firm hand to guide the project, the proposals could easily have become lost amongst the papers of the overworked War Office and disappeared from view, or else have languished in forgotten obscurity on the cluttered desks of important figures.
Fortunately for the British the vehicle had two enthusiastic champions. Churchill had immediately seen the potential in the device and supported it throughout its creation, but his influenced waxed and waned with the fortunes of his political career. However, his enthusiasm was shared by the Chief of the Imperial General Staff, Sir Douglas Haig. Haig had been promoted to the post of CIGS during the hasty command reshuffle that took place in the aftermath of the Curragh incident of early 1914. Although desperately disappointed to be denied a combat command, he overcame his frustration by absorbing himself with his work. He proved to be a determined and energetic CIGS. Convinced that the war could only be won by defeating Germany on the Western Front, Haig was an enthusiastic supporter of new technologies that promised to break the deadlock. His fascination with innovative weapons was sometimes to his detriment, and at one point he was even taken in by a charlatan who claimed to have invented a death ray. However, when it came to the development of armoured vehicles, Haig’s instincts were correct. He saw the tank as a decisive weapon and used the strength of his position to ensure that the work was fully funded and pursued with vigour.
The British had another major advantage in their early design work. Although it had been overlooked for the better part of a year, the feasibility study on the de Mole vehicle was suddenly remembered. The report gave the wartime designers a crucial head start. Driven by Churchill’s enthusiasm and Haig’s determination, work on an armoured vehicle began in early 1915 and the project progressed rapidly. Debate followed as to its ideal size, weight, armour, and armament. Numerous tests and rigorous trials took place. The process was further complicated by the need for absolute secrecy so that the Germans would have no time to develop countermeasures.
The first fully functional prototype was ready for trials in August 1915. It was a caterpillar-tracked, rhomboid-shaped vehicle with room for heavy weapons in side sponsons and machine guns in its central hull. It was a slow-moving and somewhat crude machine, but it was also a revolutionary weapon. Having passed its trials, the tank was demonstrated to senior government and military figures. Ernest Swinton remembered: ‘it was a striking scene when the signal was given and a species of gigantic cubist steel slug slid out of its lair.’ The display was impressive. One observer commented, ‘wire entanglements it goes through like a rhinoceros through a field of corn.’ There was one burning question that was raised by the army representatives: ‘How soon can we have them?’ The Ministry of Munitions thought it could have fifty tanks ready by early 1916 with more to follow.
Yet armoured innovators, including Swinton and Churchill, urged that the army should be patient and not launch a premature attack with a handful of machines. It would be better to build up the armoured branch until it was powerful enough to strike a decisive blow against the German line. Their views found favour with Field Marshal Sir Horace Smith-Dorrien. Smith-Dorrien had been promoted to full command of the British Army in France in mid-1915 and he had been searching for innovative ideas for breaking the deadlock ever since. The development of the tank had enormous promise. However, Smith-Dorrien knew that the matter could not be rushed. Earlier in the war he had criticised the hasty deployment of undertrained infantry. He would not see the same mistake made with the new armoured branch. Time was needed to train the crews and devise tactics for the vehicles. Although the temptation to deploy them immediately was very great, Smith-Dorrien made the bold decision to hold back the tanks until they were adjudged to be battle ready.
The vehicles were assigned their own organisation that could coordinate command, training, and operational planning. To maintain secrecy, the tanks were formed into the Heavy Branch of the Machine Gun Corps. In the meantime designers, crews, and commanders worked feverishly on all aspects of the new arm. Tactics had to be devised entirely from scratch and crews had to be trained in the use of the new machine. The designers tested and refined the MK I tank, correcting problems, adding features, and producing improved versions. There was also some interchange of ideas with the French, who were working independently on their own tank designs.
In September 1916 an agreement was reached between the British and French armies: neither side would deploy their tanks until the other was ready, thus ensuring that their combat usage came as an unpleasant surprise to the Germans. The decision would have important consequences.
April 1917: Allied Plans
April 1917 was to be a critical month in the Allied war effort. The German retreat to the fortifications of the Hindenburg Line, although strategically sound, also revealed that the battles of 1916 had inflicted serious damage on the German Army. After a relative lull during the bitterly cold winter months, the dawning of the spring signalled that it was time for the British and French to renew the offensive and hurl the invader back to his own borders. To do this, they would deploy their carefully prepared secret weapon.
Tanks had been gathering behind Allied lines throughout late 1916. Officers had the chance to inspect them, and tank commanders had the opportunity to work with the infantry that they would be supporting in battle. Every effort was made to maintain secrecy during this assemblage. Tanks were concealed in aircraft hangars, in wooded areas and even in disused railway tunnels to keep them from the prying eyes of German reconnaissance aircraft. Despite the best efforts of the British, the Germans gathered some inkling of the new machines. Remarkably, this information had virtually no influence on their military planning. General Erich Ludendorff paid them no heed, prompting Churchill’s postwar assessment that when it came to tanks, ‘the ablest soldier in Germany was blind’. At the front line there were vague warnings that the Allies were preparing ‘land cruisers’ for their next offensive. However, what these machines looked like or were capable of remained a mystery, and the Germans were taken completely by surprise when the tanks finally attacked.
It was decided that April would be the month when the tanks were to be unleashed on the enemy. The French intended to deploy their own vehicles in support of their massive offensive against the Chemin des Dames. The British had agreed to play their own role in supporting this operation by attacking around Arras. There was an optimistic hope that if both British and French attacks broke through then they would drive onwards to link up deep in German-occupied territory, outflanking the Hindenburg Line at a stroke. More realistically, the British attack would draw in German reserves and distract attention from the heavy French assault.
The German position around Arras was anchored on the dominating heights of the Vimy Ridge to the north and on the sophisticated defences of the Hindenburg Line at Bullecourt to the south. The trench lines were constructed in depth and the position stretched back some ten thousand yards. Faced with these strong defences, the British had assembled approximately five hundred battle-ready tanks. The majority of the vehicles were MK I and MK II tanks, little changed from the first prototype that had been demonstrated in September 1915. However, a significant proportion of the force consisted of the more sophisticated and reliable MK IVs which had only recently rolled off the production lines.
The Battle of Arras would be defined by surprise. Unlike earlier battles, which had been characterised by bombardments lasting a week or more, the Arras attack was to be preceded with a short but intense bombardment of no more than forty-eight hours. As soon as the barrage lifted, the tanks would lead the assault on the German line, crushing any unbroken wire beneath their tracks and making a path for the infantry. Surviving German strongpoints would be destroyed by the 6-pounder guns carried by the ‘male’ versions of the tanks, whilst the machine-gun-armed ‘females’ would mow down any German counterattacks. The British infantry would surge forward to consolidate the ground and continue the advance. The Battle of Arras represented a remarkably ambitious plan and its reliance on an entirely untried weapon was unprecedented in the history of warfare. The Heavy Branch was about to receive its baptism of fire.
The British attack had originally been planned for 9 April but the assault was delayed for three days due to unusually poor weather. It was bitterly cold when the battle began on 12 April and many accounts recalled the sudden snow flurries that swept across the area.
As planned, the Royal Artillery had opened the fighting with an intense bombardment. After forty-eight hours of constant shelling the fire reached its crescendo, the gunners labouring feverishly to work their guns, with many stripped to the waist despite the unseasonable cold. As its final act, the artillery smothered the German position with a mixture of dense poison gas and choking black smoke, blinding the defenders to ensure that they would not see the approach of the tanks until it was too late.
Tanks were carefully concealed all along the British line and their commanders nervously counted down the minutes until zero hour. Although thoroughly trained, none of the crews had any real idea what to expect. Some crewmen had battle experience in other arms of service, but this was the first time any had seen actual combat from the inside of their vehicles. One veteran recalled a tank commanded by a young second lieutenant who had ‘never seen a shot fired in his life’ but who was determined to ‘attack Germany all on his own’ by ‘shooting at every living thing he saw’.
At zero hour the tanks lurched forward from the British trenches. The advance seemed painfully slow. Some tanks failed to move from their start positions due to engine failure or the driver ‘missing the gears’. Others lumbered forward a short distance before experiencing similar breakdown or else becoming stuck in soft ground. The ironclad line was ragged in places. The clouds that blinded the German defenders would not last forever. Infantrymen strained to get forward and ahead of the slow-moving machines, not wanting to be caught in no man’s land when the Germans recovered their wits.
Yet, although it was slow, the tank attack had a relentless quality. The vehicles clambered through shell holes and over battlefield detritus. Suddenly, they had reached the wire belts – already thoroughly mangled by the British bombardment – and crashed through the steel defences without pause. One crewman remembered the sound as his tank crushed the obstacle: ‘It screeched against the hull … snapping and scraping, snapping and grating, it eventually fizzled out and we had got ourselves through.’
Peering through the thick lenses of their gas masks, the German infantry in the front line witnessed an amazing – and appalling – sight. Dark, mechanical shapes were emerging from the smoke. The growl of their engines and the grinding of their tracks were audible even above the din of battle. As the machines approached, their hulls were suddenly lit with flashes as their numerous guns opened fire. The dreaded materialschlat – the ‘battle of equipment’ – had taken on a new and terrible form.
The defenders were stunned. A British officer recalled with quiet understatement: ‘The Germans … were too staggered at the sight of the tank to make much resistance.’ Many surrendered on the spot, and those who did not were powerless to resist the tanks and the infantry that followed close behind. The tanks rumbled over the trenches and beyond, leaving behind small parties of infantry to mop up in their wake.
Yet not all the defenders were numbed by the experience. Runners sprinted down communication trenches to warn the rear areas of the approaching metal monsters. Infantry officers snatched up field telephones, bellowing for immediate artillery support to stop the fabled ‘land cruisers’. At the other end of the line, the German gunners gritted their teeth against the brutal British counter-battery fire and responded with every gun they had.
The tanks pushed forward, moving even deeper into the German position. Shells began to burst around them. Shrapnel from near misses rattled against the hull. Direct hits proved fatal, igniting the vulnerable fuel tanks and reducing tanks to burning wrecks. German machine-gunners fired entire belts of ammunition at the tanks, hoping to find a weak point. Although most bullets bounced off the armour, these bursts of fire shattered vision periscopes, rendering the crew effectively blind. Even worse was the previously unknown effect of ‘splash’: bullet impacts on the exterior of the tank caused interior armour to flake, hurling tiny pieces of hot metal into faces of the crew. A tank commander remembered ‘a smash against my flap at the front caused splinters to come in and the blood to pour down my face. Another minute and my driver got the same.’ In places German infantry assaulted isolated tanks directly, attempting to tear open the crew hatches, thrusting bayonets through vision slits and jamming grenades between the tracks.
The attackers steadily lost vehicles, some knocked out by enemy action, others suffering breakdowns, or ditching in shell holes. But the remaining tanks ploughed forward, pressing ever deeper into the German defensive system. In the skies overhead Royal Flying Corps observation aircraft watched and reported on the advance. Vimy Ridge fell to the triumphant Canadians, whilst the Australians captured Bullecourt with the aid of dozens of tanks. With the flanks secure, the British attack drove deep into the central German position. The haul of prisoners was immense.
However, the attack gradually lost its momentum. Although the tanks could pass through German shelling to an extent, their supporting infantry and cavalry were not so fortunate. As a result leading tanks became isolated and were either forced to fall back or else be overrun by German attacks. As evening approached it was clear that the attack was petering out and it was decided to consolidate the gains and prepare for a renewed advance the following day.
The British Army had made the deepest advance against a German position since the dawn of trench warfare, with some spearheads reaching the very last of the defence lines before they were forced to stop. Key positions had been taken at a comparatively low cost in lives. Thousands of German prisoners had been captured. For the first time in the war, church bells were sounded across Britain to signify a great victory.