Famous Tank Battles

By the evening of the twenty-first of November, Nineteen Seventeen, the Battle of Cambrai had changed character. What had begun as a brilliantly fast assault against the Hindenburg Line was no longer simply about how far the British could keep moving in every direction. It had become a harder question of choice. Commanders had to decide where the remaining possibility of success actually lay, and where energy, men, tanks, and time were now being wasted against obstacles that could not be mastered quickly enough. The decision to turn west toward Bourlon Ridge was therefore not a dramatic change of mood or an act of battlefield whim. It was the result of a day and a half of combat that had revealed, with painful clarity, which opportunities were widening and which were narrowing.

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The original British design helps explain why that choice mattered so much. The battle had never been intended as a simple straight drive toward Cambrai itself. It involved two linked operational aims. One was to secure the right flank along the Bonavis Ridge and the line of villages and crossings around places such as Crévecoeur and Rumilly, so that any advance would not be exposed to a sharp German reply from the southeast. The other was to establish the British firmly on the dominating high ground from Fontaine-notre-Dame to Bourlon and Moeuvres, because that ridge would provide observation, tactical control, and a platform for further action to the west and north-west. These aims supported one another on paper. If both could be reached quickly, the British might hold the breach open long enough to exploit it. If one failed badly enough, the whole shape of success would begin to distort.

At first, the eastern side of that design still seemed alive. Masnières had been cleared of the enemy during the evening of the twentieth, and on the next day British troops attacked east and north of the village while other formations tried to extend the success along the canal zone. For a few hours, the logic remained attractive. If the crossings could be secured and the right flank pushed outward toward Rumilly and the river line beyond, then the opening gains in the center might be protected and perhaps enlarged. This was not fantasy. It followed directly from the battle plan. The British had already shown that the forward trench systems could be penetrated. What they now needed was a wider, safer opening through which reserves, cavalry, artillery, and support could move without being strangled by the terrain. That is why the eastern effort still mattered on the twenty-first. It offered the hope of turning a violent penetration into something more stable and more dangerous for the Germans.

But the battlefield east of the canal would not cooperate with that hope. The broken bridge at Masnières had already shown how fragile the route structure really was, and the events of the twenty-first made the problem even clearer. A crossing that looks manageable on a planning sketch can become operationally useless if it cannot carry enough force, quickly enough, under fire. British infantry could still get across in places. Local gains could still be made. Yet piecemeal passage was not the same thing as an exploitation route. Tanks could not flow there in strength, cavalry could not be passed over with the mass and speed the plan required, and every attempt to push farther ran into the hard fact that a breach is only as useful as the roads, bridges, and approaches behind it. Once that truth became undeniable, the eastern attack began to change from opportunity into burden.

The evidence of that narrowing came quickly and from several directions at once. British troops did make local progress east of Masnières, and they briefly seized ground that seemed to push the right flank outward. Yet German resistance stiffened rapidly. Counterattacks from the direction of Rumilly showed that the enemy was already recovering enough control to contest every fresh step. Gains at places like Les Rues des Vignes could not always be held, and toward Crévecoeur the British found that crossing the canal zone was not the same thing as forcing passage beyond it. Machine-gun fire, local defensive organization, and the simple difficulty of feeding strength across a narrow obstacle turned each advance into a separate fight rather than part of a widening operational flow. That difference mattered enormously. Once the eastern front became a collection of local struggles instead of a sustained thrust, it stopped being the place where a decision could be won quickly.

Exhaustion made the matter even more decisive. The troops engaged near Marcoing, Masnières, and the approaches beyond had already fought through the shock of the first day and then been asked to continue the pressure without any real pause. Their tanks were thinned, their support was difficult to move forward, and the infantry had been carrying the burden of village fighting, crossing attempts, and repeated counterattacks. Command decisions are often described as if they emerge from maps and abstractions alone, but they are also made from bodies that have reached their limit. The British command did at first consider renewing the effort toward Rumilly on the following day. Yet by the night of the twenty-first that intention had to be canceled because the troops on that axis were too exhausted to do what the plan still demanded. That cancellation was more than a detail. It was a recognition that the eastern push was no longer an operational spearhead. It had become a front to hold, not a front to enlarge.

At the same time, events farther west had altered the picture in the opposite direction. The capture of Flesquières on the morning of the twenty-first removed the most disruptive obstacle that had limited the first day’s results in the center-left. Once that village was gone from German hands, the British line of advance in that sector became less jagged and more coherent. Then the British pushed again toward Anneux, Cantaing, Fontaine-notre-Dame, and the approaches to Bourlon Wood, with tanks and cavalry cooperating in support of the infantry. Here, unlike at the canal, the battle still seemed to offer a living chance. The western ground was not easy, and the fighting there would soon become vicious, but the axis itself still promised something that the east no longer did: room to seize the dominant tactical feature that governed the whole battlefield north and west of the breakthrough.

Bourlon Ridge mattered because it was not merely another objective to be ticked off after the first day. It was the high ground that overlooked much of the ground the British had already won and much of the ground they still hoped to control. Whoever held it could observe movement, direct artillery more effectively, and anchor a position that otherwise risked becoming a vulnerable salient jutting into German-held country. This point is easy to underestimate because “ridge” sounds static, almost defensive, beside the more dramatic image of cavalry riding through a breach. But at Cambrai the ridge was the decisive remaining terrain. If the British could seize it, their gains might be consolidated on terms favorable enough to withstand counterattack and perhaps support further operations. If they failed to seize it, then much of the ground won in the opening assault would remain exposed to German observation and reply. In a battle that had begun with movement, high ground suddenly became more important than distance.

There was also a strategic clock ticking under all of this. British planning had assumed that the Germans would need roughly two days before reserves arrived in truly formidable strength. By the evening of the twenty-first, that window was effectively closing. That changed the nature of choice. A commander may attack in two directions when the enemy is still reeling, but once reserves begin to enter the battle in force, dispersion becomes much more dangerous. The British no longer had the luxury of treating east and west as equally promising. The eastern option required stronger crossings, fresher troops, and more time than the battlefield was now offering. The western option required immediate hard fighting for high ground already within reach, before German reinforcement and reorganization made even that attempt prohibitively costly. In other words, the turn westward was not simply preference. It was a response to the shrinking number of things that still looked attainable before the battle settled into a new and much harder phase.

This is why the decision should not be read as pure offensive optimism. It was also an act of defensive prudence. If the British held on to the gains around the canal while leaving Bourlon Ridge in German hands, they risked keeping a salient whose northern and western shoulder remained dangerously exposed. Ground won by bold assault can become a trap if it is overlooked by enemy positions and bounded by narrow communications routes. Commanders at Cambrai were beginning to see that problem clearly. The east was not just difficult to push from. It was awkward to support and vulnerable to counterattack if the broader shape of the salient was not improved. Turning toward Bourlon therefore meant more than chasing one last dramatic success. It meant trying to secure the battlefield geometry of what had already been won before the Germans were fully ready to challenge it.

The cost of that choice was that the battle would now move into very different terrain and into a very different style of fighting. The opening assault of the twentieth had depended on surprise, broad-front shock, and the rapid penetration of trench systems. The struggle for Bourlon Ridge and its woods would be harder, closer, and more attritional. Woods break up visibility, complicate artillery support, and reduce some of the advantages that tanks had shown so clearly on the first day. Villages like Fontaine-notre-Dame and Bourlon itself could be fought over repeatedly, and the ridge could absorb reinforcements on both sides rather than collapsing all at once. Yet for British commanders, this hard western fight still looked more meaningful than continued effort across the canal. The east had become a place where success was narrowing into local endurance. The west remained a place where one important tactical success might still alter the shape of the whole battle.

That contrast reveals something essential about Cambrai and about the evolution of armored warfare more broadly. The British had learned how to crack open a fortified front. What they had not yet mastered was how to convert that rupture into a deep and sustained exploitation when the routes beyond the front depended on a few vulnerable crossings and when the forces meant to pass through them lacked the speed, communications, and engineering flexibility that later mechanized armies would take for granted. The decision to go west was, in one sense, an admission of that limit. The cavalry could not finish the battle across the canal. The crossings could not feed enough force quickly enough. The right-flank push could not be renewed by exhausted troops against a recovering enemy. So the commanders turned toward the terrain that still offered immediate tactical value, because the more ambitious eastern option had already been quietly defeated by delay.

By the evening of the twenty-first, then, British commanders were not choosing between two equally open roads to victory. They were recognizing that one road had narrowed into a series of costly local fights while the other, though difficult, still led toward the commanding ground that might justify holding and perhaps extending the salient. That is why the turn toward Bourlon Ridge was so important. It marked the end of Cambrai’s most fluid moment and the beginning of its next, harsher phase. The battle had shown that the line could be broken. Now it was showing that the battlefield beyond the breach could still force a commander back into the old discipline of priorities, terrain, and limited means. The resumed westward thrust after Flesquières fell, the failure to force a stronger passage beyond Masnières and toward Crévecoeur, the cancellation of the Rumilly attack because of exhaustion, and the recognition by the evening of the twenty-first that Bourlon still had to be taken before the reserve window fully closed are all reflected in the contemporary dispatch and later battle summaries.