Battle of Cambrai

The Battle of Cambrai was fought between the British and German forces on the Western Front of World War I. It consisted of a British attack, followed by an immediate German counterattack, the largest one on the Western Front since 1914. Cambrai, an important supply point for the German Hindenburg Line, was attacked with a combination of artillery and tanks which were meant to raid the enemy positions. After an initial success on the first day, the weaknesses of the tanks made progress slow to a crawl. The rapid mobilization and efficient counter-stroke gave the Germans hope that they could achieve victory before American mobilization could overwhelm them.

Although its morale and manpower were stretched almost to breaking point by the fighting at Ypres, the British Expeditionary Force nevertheless made one more offensive effort in 1917. At Cambrai, the British concentrated their tanks so that, for the first time, they were deployed for a mass attack rather than being scattered in small groups along the front for local infantry support.

There remained one means of offence against the Germans that the mud of Flanders had until now made impossible: machine warfare. The main reserve of the Tank Corps, built up incrementally during 1917, had therefore remained intact. Its commander, Brigadier General H. Elles, had been seeking an opportunity to use it in a profitable way during the summer and had interested General Sir Julian Byng, commander of the Third Army, in the idea of making a surprise attack with tanks on his front, which ran across dry, chalky ground in which tanks would not be bogged down.

The assault at Cambrai evolved from a Tank Corps plan for a large-scale raid, the chief object of which was not to seize ground but to deal the Germans a bruising blow on terrain which, unlike the Ypres Salient, actually suited tanks. The Third Army staff expanded the scheme, transforming it into a major operation against the Hindenburg Line.

Since part of the Imperial General Staff’s misrepresentations to the War Cabinet involved suppressing the actual status of the French, who under Philippe Pétain had by now completed three offensive operations on the Western Front, it was hardly possible to mount a large joint operation without embarrassing questions being asked — or embarrassing comparisons being made, as after the Somme. The BEF now had a sizable tank force, and the ground around Cambrai was eminently suitable terrain as well.

Compared to the Somme and Third Ypres, where there had been no meaningful advance at all, Cambrai at first looked like a serious breakthrough. The offensive rolled right through the German lines and got to within a few kilometers of Cambrai. From that point on, Cambrai developed into the usual attack and counterattack tactics of the previous battles.

The underlying impetus for what became the Battle of Cambrai was provided by an artillery specialist called Brigadier General Hugh Tudor. He conceived a plan to capitalise on the vast improvements in artillery tactics and techniques, combined with the potential to use tanks, to reintroduce surprise attacks to the Western Front battlefields. The ultimate scheme was ambitious, embracing the capture of both the German First and Second Line Systems, the crossing of the St Quentin Canal, all followed by a cavalry advance to take the railway junction at Cambrai and the tactically significant Bourlon Ridge which glowered down on the whole sector.

Accurate surveying of the Western Front had been completed by 1917. This enabled a battery position and its target to be pinpointed on the map. This was then combined with the careful calibration of every gun to enable the gunners to make the correct adjustments to allow for defined error. All this meant that the artillery could suddenly open fire with a reasonable degree of accuracy. This ‘shooting off the map’, or predicted fire, could be done without previously registering the targets – something which had previously alerted the Germans to an imminent attack.

Tudor was unknowingly following a path of development similar to that of his German counterpart, Lieutenant Colonel Georg von Bruchmüller, who was engaged in similar experiments on the Eastern Front. The support of Douglas Haig, the BEF commander, was easily secured. He was not only in need of a morale-boosting success after the Third Ypres Offensive, but he also realised that the German forces would have been thinned out at Cambrai to reinforce the Ypres area.

The new artillery technique was then combined with the proven ability of tanks to flatten barbed wire, thereby avoiding the need for prolonged barrages to cut the wire for the infantry. This scheme and another idea for a 48-hour tank raid from the staff of the Tank Corps were swiftly welded together by the staff of the Third Army holding the Cambrai front.

Secrecy and speed would be all-important for the assaulting force of six infantry divisions, three tank brigades (476 tanks) and five cavalry divisions of the Cavalry Corps. After forty-eight hours the operations would be closed down if results were not satisfactory. There were no available reserves and this shortage of resources had been exacerbated by the despatch of two British divisions and heavy artillery batteries to the Italian Front.

Haig perceived advantages in a plan which might not only rebuild the BEF's reputation and revive morale but also simultaneously draw the enemy's gaze from the Italian Front, where the Italians had suffered a near-catastrophic defeat at Caporetto. The plan combined some promising tactical elements. These included the decision to abandon the customary long artillery preparation and to permit the supporting guns to deliver a surprise hurricane bombardment, capitalising on the new technique of 'predicted' shooting without prior registration of targets.

The problem with Cambrai was that the front was too narrow, and it was too constricted. There were canals on both sides of the front, so the attack, if successful, would be hemmed in. Moreover, for the attack to be successful in breaking through to Cambrai, a good twelve kilometers behind the lines, there had to be a massive follow-up, a task which General Émile Fayolle, with justification, had termed ‘moving an army through an army’. This was not simple.

French General Ferdinand Foch realized that mounting an offensive with both sides hemmed in by canals was a bad idea, and said so. The British Cabinet only learned this alarming bit of news well after the fact.

Fayolle had also observed that this business of moving one army through another was far from simple. If the attack was successful, there was room to maneuver through and spread out. At Cambrai, the BEF was in the position of having to move everything through a bottleneck created by the canals. Not only was there not enough room to do this, but Haig lacked the troops.

There were three successive German lines, and it was intended to break through them all in a single bound on the first day. Because the Cambrai front had long been quiet, it was garrisoned by only two divisions, the 20th Landwehr and the 54th Reserve, supported by no more than 150 artillery guns. German troops in defensive positions had developed a series of nasty ways in which to disable tanks.

The 20th Landwehr was classified ‘fourth-rate’ by Entente intelligence. Unfortunately for the British, the 54th Reserve, a better formation, was commanded by General von Walter, an artilleryman who had, unusually among German soldiers, taken account of the tanks' potentiality, and trained his gunners to engage moving targets from protected positions. Walter's keen interest in tank operations – at a time when the German army had no tanks – was to be of the greatest influence on the outcome of the battle.

The Germans had withdrawn to a line about twelve kilometers to the southwest of the town during February and March 1917, and so the ground behind the German positions was rolling pasture, not some moonscape full of refuse and water-filled craters. The ground over which the tanks would advance was in good shape as well.

The new light mortar, in widespread use by the infantry since the end of 1915, could disable one of the slow-moving behemoths, while the 12.98-millimeter rifle the Germans had already been using in small quantities to shoot through armored loopholes fired an extremely potent armor-piercing bullet. Since the Germans had already integrated their field artillery and their infantry into joint operations, gunners could also be relied on to destroy tanks: the ordinary 77-millimeter field gun had enough punch to blow a hole through the thinly armored vehicles.

The Germans had been working on tank development for over a year. There were two reasons for their slow progress. One was that the Germans realized the power-to-weight ratio problem and were trying to get around it by coupling two engines together. The other reason was that after each engagement the battlefield was littered with abandoned Entente tanks: as such they could repossess and study the enemy tanks. The first working German vehicle was in service by February 1918.

Although the guns amassed for the barrage would be the key to success, another early focus of attention was inevitably the mass use of tanks. A workable system had to be hammered out to get the tanks across No Man’s Land and the gaping trenches of the Hindenburg Line. One crucial advance was the reinvention of the fascine for the mechanical age – a huge roll of tightly bundled brushwood carried on the roof of the tank which could be dropped ahead of it to provide safe passage over a German trench.

The infantry had to be trained to work in conjunction with the tanks and vice versa, communication still being a problem: ‘A day came when we moved from our camp to a battle front in miniature – a series of trenches defended by rows of barbed wire. Several tanks were already there in attacking position. We lined up behind them and followed them to see, to our astonishment, these massive new and mysterious machines stride over the wire, crushing it into the ground as if it was so much waste paper. Then as we continued to follow, our amazement increasing, they surmounted the huge trenches, without effort, turning to bring their deadly quick firing guns and their Lewis guns to bear upon the defenders. Of course, there were no defenders, but the lesson was clear. No defences, however strong, no machine-gun fire or small arms fire, etc., would stop these thickly armoured monsters, driven forward by their powerful engines whose deep throbbing was music to our ears. Only a direct hit by shell fire would stop them as it would stop anything.’ (Private William Kirkby, 2/6th West Yorkshire Regiment)

The mechanical reliability, cross-country capabilities and speed of the British tanks had been much improved since the Somme. The British Tanks Corps now learned exactly the same lesson that the French had learned six months earlier. Half of the underpowered and unwieldy monsters were destroyed or abandoned on the battlefield, with about sixty being picked off by German gunners. Tanks, like heavy guns, wear out with use, and the first tanks wore out quickly and needed refitting.

Three hundred and seventy-eight fighting tanks, all carrying large brushwood bundles or fascines to assist them in crossing trenches, would operate in groups of three. In each group, an 'advanced guard' tank would move 100 yards ahead of the two main body tanks, its task being to subdue German fire and protect the two following tanks. The latter would lead infantry sections through the German wire and over the opposing trenches. Ninety-eight supporting tanks carried supplies, bridging material, telephone cables, wireless or grapnels for hauling aside barbed wire.

The failure of comprehension of the tank's potential on the part of General George Montague Harper, commanding the 51st Highland Division, the infantry formation at the centre of the front of attack, was crucial. Harper, brave but conventional, did not like tanks but loved his Highland soldiers. He had formed the view that tanks would attract German artillery fire on to his infantry and so, instead of insisting that they follow closely, ordered them to keep 150-200 yards behind. The resulting separation was to spell doom to the British attack at the critical moment of the battle.

When the British opened up their barrage at 06.20 on 20 November, it crashed down on the German lines and artillery batteries, while the creeping barrages preceded the advance of the infantry and the rumbling tanks. The Germans fell back, hoping their wide trenches would thwart the tanks: that would not be the case. Now the Germans were also harassed from the air. The men of the Royal Flying Corps, who had become increasingly involved in ground-strafing operations, were flying ahead of the tanks.

‘A wounded man from 7th Company approached us from the right and gasped a few heavily charged words, “The British have got tanks!” A cold shiver ran down my spine; the effect of this information on the morale of my men was plain to see. They, who had just been pouring scorn on the British, saying that they would all be tearing their trousers on our barbed wire, suddenly looked disconcerted. All of a sudden there was a muffled shout from a neighbouring sentry post. Everyone rushed to the parapet and then we saw, looming out of the swirling fog, a dreadful colossus heading straight for us. Every single one of us could almost hear his heart beating in his chest! However, we were seized only momentarily by leaden indecision. With weapons tucked into our cheeks we fired shot after shot at the enemy. Unfortunately, this affected them not in the slightest. Slowly, but unstoppably, they drew closer. Firing also began left and right of us. As I pulled myself up to look over the parapet, I could see a whole chain of these steel monsters advancing towards our trenches. The tank to our front was barely a hundred metres away by now. The light machine gun had fired off its last belt of ammunition without visible effect. What was to be done?’ (Second Lieutenant A. Saucke, 84th Infantry Regiment)

It was in the trenches, though, that the fascines proved their worth, as a stunned Lt. Saucke watched on helplessly: ‘I watched one tank, which displayed a white flag as a special recognition mark and had some sort of attachment on its front. It approached the trench at right angles, then, when it reached the lip of the trench, the attachment suddenly fell vertically. I assumed that the tank had been hit or at least damaged and could scarcely believe my eyes when it continued onwards and its outline gradually became more clearly defined. There could be no doubt, it had crossed the trench and was pressing on towards us. What I had seen must have been a large wooden object or a great bundle of sticks which it had released at the appropriate moment in order to cross the trench. The following moments were difficult. We felt betrayed and sold out. Once more the most violent firing broke out as every barrel was brought to bear against these monstrous opponents. If only its infantry had put in an appearance! We could have dealt with men of flesh and blood like ourselves, but we were defenceless against these armoured machines.’

One of the RFC men was Second Lieutenant Arthur Gould Lee, who had been despatched to bomb a battery of 5.9-inch guns. The aircraft may not have carried a significant payload of bombs, but the impact of swarms of busy-bee scouts was disruptive. And some of their little bombs struck home: ‘Smoke shells burst ahead, a flash of red flame and masses of belching cloud, which we speed through – nauseous-smelling stuff that stings the eyes. In patches, where smoke merges with mist and cloud, we fly blind. Now we reach the rear of the Hindenburg defence system, two lots of trenches, with troops in field grey waiting in them, their forward view blocked by the pall of smoke. We skim just over their heads, I see them staring up at us in incredulous amazement. More smoke shells burst ahead, and suddenly, unexpectedly, we’re at the wood. The 5.9s below are firing, producing more smoke. So there we are, the three of us, whirling blindly around at 50–100 feet, all but colliding, being shot at from below, and trying to place bombs accurately. In a sharp turn I saw a bunch of guns right in line for attack, so dived at 45 degrees and released all four bombs. As I swung aside I saw them burst, a group of white-grey puffs centred with red flames. One fell between two guns, the rest a few yards away. Splinters suddenly splash in my face – a bullet through a centresection strut. This makes me go hot, and I dive at another group of guns, giving them 100 rounds, see a machine gun blazing at me, swing on to that, one short burst and he stops firing. As I climb up, a Camel whizzes past me out of the mist, missing me by a yard. It makes me sweat with fright. This is too dangerous.’

Inside the tanks the crews were achieving great things, but at the same time were enduring a tremendous physical and mental trial: ‘I fired at anything I could see that looked like a target, any rise in the ground, trench, bush, anything that might shelter someone and I dropped most of the empty drums out of the flap in front. By now the inside of the tank was terribly hot, caused by the engine chiefly and the air was heavy and close, and caught your throat when you breathed; this, owing to the back-blast of the two guns and the ejector of the machine gun, and the noise was appalling.’ (Lieutenant Kenneth Wootton, ‘Apollyon II’, ‘A’ Battalion, Tank Corps)

Tanks were superb weapons against demoralised infantry, but they were also large, slow-moving targets which were themselves vulnerable to artillery fire: ‘Soon after we came almost face to face with at least four more guns, also in the open. All pointing in our direction. They fired at me, just point blank, and the shell struck us in front just where I was sitting and, bursting as it hit, blew a hole in the armour-plating by my left knee. The first thing that made me realise we had been hit was “coming to” finding myself lying back over my seat with my head nearly on the floor and my left foot caught in something so that I couldn’t move it. I felt no pain of any sort, being dazed and numb all over, with a tremendous sort of singing noise in both ears and some blood running into my left eye, which I wiped with my hand now and then. I slid back off the seat and sank to the floor having no use in my legs or arms, but still feeling nothing.’ (Lieutenant Kenneth Wootton, ‘Apollyon II’, ‘A’ Battalion, Tank Corps)

There was also a great problem getting the tanks across the St Quentin Canal. After a vigorous exchange of fire between tanks and German infantry in the cottages opposite, the Flying Fox II, festooned with infantry, tried to cross an already partially demolished bridge: ‘Swinging to the right again, we started across – going strong and no one hurt except odd splinters. We had almost got across, when “Grruff Crash!” – the Bosche blew the far end of the span in, and we dropped smack into the canal. We thought the end of the world had come at least, but had the presence of mind to fling open all exits, and the water started to pour in from all directions. The air inside was thick with ammunition boxes and shells which had broken loose from their holders with the shock of landing, and flew about in all directions. Something outside hit the muzzle of my gun, and as the traversing arm was under my armpit, it lifted me up, bringing my head into violent contact with the steel plating of the roof. I was thankful that I was wearing a steel helmet at the time. Luckily, our tail had lodged on some masonry, and so held the rear end of the tank out of the water. I was delayed a few seconds by the tap I had received on the head, and in the meantime the others had “shot” out of every exit, and jumped and scrambled until they gained the road, down which they “beat it” in great style.’ (Private Alfred Ballard, ‘Flying Fox II’, ‘F’ Battalion, Tank Corps)

The surprise achieved by the sudden bombardment and the employment of massed tanks enabled the British, in most places, to break through the Hindenburg front and support systems. However, in the left centre, the 51st (Highland) Division failed to take the key village of Flesquieres on the first day. Many of its accompanying tanks either broke down short of the objective or were disabled by German gunners who had been specially trained in anti-tank defence.

In the end the Front Line System of the Hindenburg Line was overrun to a depth of some 3-4 miles, a good achievement equal to the first day at Arras. On the other hand, the cavalry were unable to deploy forward to any effect: the German Second Line System between Masnières and Beaurevoir remained intact, the key bridge across the canal had been destroyed and the heights of Bourlon Ridge remained in German hands.

The British had suffered some 4,000 casualties but had taken over 4,000 German prisoners. Significantly no less than 179 tanks had been put out of action or broken down.

Given the disasters of the past, a quick advance of ten kilometers on a front of any size was an immense victory. Church bells were rung. The Hindenburg line had been broken. The Germans had at last been defeated. In England the bells rang out for a victory, the first time they had sounded since the beginning of the war. Reality was rather more distressing. The celebration was premature. Byng's cavalry, which had picked its way across the battlefield in the wake of the tanks, was held up by wire they had not cut and turned back. His infantry nudged their way forward in the days that followed.

On the following day, the offensive carried on, but by now both sides found themselves in a more familiar scenario played out countless times before. The Germans rushed forward reinforcements, while the British struggled to regain some momentum. Vicious fighting took place in an effort to gain the Bourlon Ridge, but all the British had succeeded in doing was creating a vulnerable salient by the time operations staggered to a close.

There was no surprise now, the guns had been moved forward and their firing lost precision, the number of tanks was vastly depleted, the infantry were tiring and there were few reserves available. After 3 days of fighting only 92 tanks remained operational. Because the British cavalry were disappointingly unable to exploit the initial breach, the old problem of maintaining the impetus of an advance beyond the assault phase again appeared to defy solution.

The Third Army was involved in what was essentially a fierce infantry battle for Bourlon Ridge, west of Cambrai. For all their efforts, the British divisions never completely secured Bourlon village or the neighbouring Bourlon Wood and, after a week, were left holding a salient nine miles wide and four to five miles deep. An attack with nearly four hundred vehicles was initially impressive, but when, after forty-eight hours, there were only sixty or seventy still operating, armored operations in the modern sense of the word had obviously ceased.

When Lloyd George spoke of the false and misleading reports made to the War Cabinet by his officers, in one sense he was being unfair: the British High Command apparently believed that their boundless optimism represented the true state of affairs with respect to the Germans. The whole idea of Cambrai was based on the assumption that the Germans had been beaten so badly, were so weakened, that they could do little more than hold on by their fingernails. Instead, four days after the attack stalled, the Germans launched a major counterattack.

Then, too, the British were aware that the Germans had heavy responsibilities elsewhere: while the planning was going on for Cambrai, they probably knew that the OHL had mounted an offensive at Riga in early October, and had shifted troops to Italy as well. Even if they weren’t completely whipped psychologically, the British General Staff believed the Germans should have been out of men — a perennial pipe dream that never went away.

The German High Command was well aware of the opportunities presented by the newly created British salient. Some nine miles wide and four miles deep, it was vulnerable to attacks from both flanks to pinch it out, thereby cutting off the units holding the extremities. Soon preparations were underway for a major counterattack by the Second Army led by General Georg von der Marwitz. The end result was a plan to fire a diversionary barrage at Bourlon Wood, before attacking the southern front of the salient, driving in towards the north. The German response typified the endurance of the German Empire. Despite all the trials of the year, they still managed to scrape together a formidable force of eighteen divisions, of which ten were still largely unaffected by the recent debilitating battles on the Western Front.

The German offensive tactical approach had been refined through the long years of war: their own experiences at Verdun and on the Eastern Front were melded with what they had observed in their British and French opponents.

The German High Command still perceived no pressing need for tanks, and continued to rely on their massed artillery, now equalled by the British, but still a devastating weapon of war. There would be a short powerful bombardment, targeting in particular batteries and headquarters, cutting communications routes and generally isolating the salient, while the ubiquitous high-angle mortars pummelled the front lines to great effect. The infantry would then advance, once again trialling the stormtrooper tactics that were still being refined.

The first wave of infantry would move forward in sections, using light machine guns, grenades and flamethrowers, passing between strong points, feeling their way through the cracks in the British defences, seeking out the vulnerable artillery batteries and headquarters. Behind them would be mobile minenwerfers or mine launchers, and even some 77 mm guns to provide close support in reducing points of resistance. Above them would be swarms of low-flying aircraft strafing the British wherever they were sighted.

The German barrage began, quietly at first but soon building up to a terrifying crescendo. As the infantry advanced, they smashed through British defences. In places they even broke through to the gun line. The Third Army awoke to near disaster: all available units were rushed forward to hold key tactical positions. The fighting degenerated into a welter of attacks and counterattacks. Eventually the British pulled back in relatively good order from the extremities of the salient, to a strong defensive line based on Flesquières – and there they stayed.

Some German gunners certainly enjoyed themselves in delivering the drumfire they had endured so often from the British and French: ‘Today is our day. Today it is we who are doing the drumming. 7.50 am. The order to fire flies from the observation post to the guns. It passes along the chain of relays like a flat pebble skimming along the surface of a pond. The battery commander has lit a living time fuse. “Rumm… rumm… rumm… rumm” and simultaneously angry streams of flame belch out from behind hedges and bushes, from hollows and the ruins of houses. “Next target 3,000 metres! From the right, fire!” “Rumm… rumm… rumm…” “That is revenge for the naval guns firing on the Lorette Spur, which ploughed up our cemeteries.” “3,500 metres! Fire!” “Rumm… rumm… rumm… rumm…” That is for the autumn battles in Champagne. Now the Tommies are picking up the bill for the French. “3,700” “Rumm… rumm… rumm… rumm…” Go on, crawl away into the earth, duck down low. Revenge for the whimpering of the helpless comrades buried alive on the Somme. “3,900!” “Rumm… rumm… rumm… rumm…” Great fun, eh, Tommy? Swallow the gas and choke out your death rattles. That is for Verdun. “Rolling Salvo! 4,000 metres!” “Rumm…” Revenge for Vermelles! “3,900!” “Rumm…” Revenge for Givenchy! “3,800!” “Rumm…” Revenge for St Hilaire! “3,700!” For Fontaine! “3,600!” “3,500!” Revenge for Wavrille and Herbebois! “3,000! Rapid fire!” What fun, Tommy! We are taking our revenge for the dismal years when we had to be patient. Long, long years of being on the receiving end of drum fire, helpless. “Rumm… rumm… rumm… rumm…” Today we are doing the drumming!’ (Second Lieutenant von der Goltz, 14th Field Artillery Regiment)

As the infantry moved into No Man’s Land, they cut through the British troops, many of whom were already exhausted: ‘In no time at all we were in possession of the first enemy positions. Without pausing we assaulted the next hollow, where we came across numerous dugouts. We had soon cleared the enemy out of them. Up to this point, about 200 metres, we had doubled forward. I commanded the light machine guns, whose crews found the advance exceptionally strenuous because of their heavy loads. Despite the great effort involved, we stormed forward on to the hill to our front and, once again, we soon broke the tough defence of the enemy. We took numerous prisoners. We continued on unstoppably through the next dip, clearing the dugouts by the use of hand grenades.’ (Staff Sergeant Engesser, 40th Fusilier Regiment)

Among the British troops were the men of the Guards Division who launched a counterattack: ‘We felt “We are the Guards. We’ll show them”, and we knew we had to keep cool, and maintain a disciplined line. Orders were passed along verbally. Over undulating down we went, and still no sign of Germans, but when we drew near Gouzeaucourt Wood and, crossing a deserted trench, reached the crest of a hill, they met us with a blizzard of fire. Mates fell on all sides, and the order came to fall back to the trench. Many wounded were left behind, and I crept out and started to drag in a heavy fellow badly wounded in the legs. It wasn’t easy going and, desperately, I appealed to him, “Make an effort, chum!” “Effort be damned!” he exclaimed, and it struck me as so comic a situation, with bullets spattering around, that I had to pause and chuckle before resuming the pull to the trench. Helping hands hauled him over the parapet to safety, and that was the last I saw or heard of him. He must have been swiftly carried to the rear.’ (Private Norman Cliff, 2nd Grenadier Guards)

The British flung everything in to stem the tide: the disciplined troops of the Guards Division, low-flying strafing aircraft, the remnants of the tanks not yet withdrawn from the battlefield, dismounted cavalry, even charges by mounted Indian lancers.

The German counter-blow was perhaps most notable for the vital part played by storm troops, employing assault and infiltration tactics developed during the past two years. The timely arrival of some British reinforcements slowed German progress. But, at Haig's insistence, they fell back to a shorter and more defensible line in front of Flesquieres, thereby abandoning much of the ground originally gained.

The Germans had not only ejected the British from the forward positions gained in the initial fighting, but had thrown them out of a whole section of their start line. This was a tactic that had first been observed in the spring of 1915 during one phase of the Battle of the Woëvre at the Tranchée de Calonne: the initial French attack had been quite successful, but the defenders had promptly countered and thrown the surprised French out of the initial positions in their own line.

Neither side gained the objectives they craved; both did enough to deny their enemies success. The two tactical roller-coasters were rattling along side by side but for all their advances no one had yet solved the problem of breaking through their opponent’s lines. The battle ended with the honors shared, but both sides had trialled the tactics that would come to center stage in 1918.

Casualties at Cambrai totalled more than 40,000 on each side but the most significant feature of the battle was the fact that both the British and Germans achieved a measure of success with tactical methods which at last seemed to offer a way out of the long-standing deadlock.

The Cambrai battle, which should have yielded a deep pocket driven into the German front, ended on ambiguous terms along the line of the ‘Drocourt-Queant Switch’, a sinuous double salient which gave both the British and the Germans some of each other's long-held territory. It was an appropriate symbol of the precarious balance of power on the Western Front at the end of 1917.

The advent of predicted fire and the mass use of tanks also left a lingering sword of Damocles: no longer could any German sector be considered truly quiet. An Entente offensive could burst out from anywhere at any time and the Germans were consequently forced to strengthen their defences and review their divisional dispositions all along the line.

Inside the British military, Cambrai was seen as a near miss, and the army consoled itself yet again with its two-part fallback position. Subjectively, it was claimed the Germans were running out of fight. Objectively, they were losing the war of attrition. The argument was also made that Great Britain had no real choice, after the collapse of the French Army.

The aggressive German counterattack at Cambrai strongly suggested that the German Army was far from losing its will to continue the fight. And anecdotally, the evidence was to the contrary. One British officer saw the essential tragedy of his soldiers, and put it in his report. If his men advanced standing up, ‘they were an easy target’. But if they advanced by crawling, they ‘were exhausted in a few minutes’. ‘How the devil can we finish this war?’ General Fayolle confided to his diary.

Victory had proved as elusive as ever for the Entente in 1917. Nivelle's failure, the French Army mutinies, the misery of the Passchendaele mud and the late setback after the brilliant initial success at Cambrai all combined to cast a dark cloud over Entente hopes for the immediate future. The British Prime Minister, David Lloyd George, while still unwilling to provoke a political crisis by removing Generals William Robertson and Haig, continued to seek ways of limiting their authority and influence. So far, the assembly of United States troops had proceeded at a frustratingly slow pace. On a more constructive note, the establishment of a Supreme War Council at Versailles in November 1917 promised improved coordination of Entente strategy in the coming year.

The war correspondent Philip Gibbs observed that, for the first time in the war, 'the British Army lost its spirit of optimism, and there was a sense of deadly depression among the many officers and men with whom I came in touch'. However, a brief mutiny at the infantry base depot at Etaples in September was caused by poor accommodation and a brutal training regime at that particular camp and did not signal a major collapse in morale throughout the BEF.

The losses in the attrition battles at Arras and Ypres provided Lloyd George with yet more ammunition to use against Haig. Indeed, the news, in December 1917, that Edmund Allenby had captured Jerusalem from the Turks appeared to buttress the position of those who argued against the primacy of the Western Front.

1917 had certainly not been a year of total gloom for Haig and the BEF. The technical and tactical strides made by the BEF during the past 12 months were evident in the advance of XVII Corps and the success of the Canadian Corps at Arras and Vimy Ridge in April; in the storming of Messines Ridge in June; in General Plumer's powerful blows at Ypres in late September; and in the breaking of the Hindenburg Line near Cambrai in November. Even the clinging mud of Passchendaele could not wholly obscure the achievements resulting from the BEF's collective improvement and learning process since the Somme.

Philippe Petain's judicious blend of discipline and reform had brought the French Army back from the edge of the abyss into which it had stared during the spring and early summer. But, in spite of its praiseworthy performance in limited operations at Verdun in August and the Chemin des Dames in October, nobody was sure how it would fare if called upon to mount large-scale attacks. Petain himself remained reluctant to risk such offensives until the Americans arrived in force.

By 1 December 1917 barely four American divisions had reached France. Furthermore, General John Joseph 'Black Jack' Pershing, who commanded the American Expeditionary Force (AEF), had been strictly enjoined to keep his formations together as a distinct national army and to resist any attempt to use them merely as reinforcements for weakened French and British units.

As the German High Command read the English and American newspapers, it emerged — correctly — that they had no real offensive plans for the beginning of 1918. There would be no major offensive until the AEF was ready to go into action. The British estimated that it took a minimum of fifteen months for a newly raised division to be ready for combat. Simple arithmetic suggested that the earliest point at which the Americans would be ready was sometime in the summer of 1918.

The German Army had some reasons for optimism, at least in the short term, at the end of 1917. The new artillery and stormtroop assault tactics tested in operations at Cambrai had proved highly effective. The German formations on the Western Front were therefore retrained during the winter and were simultaneously augmented by divisions released from the Eastern Front following the Bolshevik Revolution in Russia. As 1917 ended, the Entente knew that they must expect a major German offensive in the west early the following year.

A sobering factor, however, was the knowledge that the Entente blockade was causing serious shortages of oil, petrol, rubber, horses and fodder, all of which would reduce the German Army's own ability to sustain mobile operations over long periods in 1918. Ominously, troops of a previously dependable division had stopped to loot a British supply depot during the German counter-stroke at Cambrai.

In December 1917 both Russia and Romania suspended hostilities with the Central Powers, enabling Germany to speed up the transfer of units from the Eastern Front. Thirty-three divisions were moved to France and Belgium before 1918 dawned. The Entente, in contrast, faced manpower problems.

Little immediate assistance would be forthcoming from the Americans. Pershing had only 130,000 troops in France by 1 December 1917 and all AEF divisions would require three months' additional training on arrival. For a short period early in 1918, therefore, the Germans would enjoy the rare luxury of outnumbering the Franco-British forces, deploying 192 divisions against 156.