To understand the nature and the natural consequences of the 1917 Battles of Passchendaele (12th October, 26th October and 6th November), it is necessary to first consider the terrain over which they were fought. This is clearly shown in the British Army's Ordnance Survey Map, General Classification of Ground, dated November 1917, reference Zonnebeke, Serial No. 28NE1. See below:
This map clearly demonstrates that the land - and, indeed, the Ordnance Survey map itself - is divided by a topological feature known as Passchendaele Ridge. On either side of the ridge there are large areas of interconnected waterlogged pastureland recovered over the years from a former marsh. The waterlogged areas were drained by agricultural drains, or canals. These could cope with all but the most torrential of seasonal rains. But, of course, the drains themselves were highly susceptible to damage by shellfire.
In architectural terms, Passchendale Ridge was the arch that held together the German defences in north east Flanders. Destroy this, and the whole of the German defence structure in the north would be in danger, and the route to the workshop of the German arms industry centred on the Ruhr would be exposed.
In planning the capture of Passchendaele Ridge, The Commander-in-Chief of the British Expeditionary Force (BEF), Field Marshal Sir Douglas Haig, and his staff made two major errors of judgement.
Firstly, their anticipation of just how much seasonal rain there would be during the 1917 offensive was far too optimistic - a sort of 'God Only Knows' situation, that in the event went against them. They were warned of the potential heavy rains of autumn, and the unpredictability of the rainfall in the months of July and August, but chose, as usual, to err on the side of optimism. In fact, in four days at the beginning of August 1917 there were 76cm (3-inches) of incessant rain.
Secondly, the pre-offensive 10 days of shelling was completely inappropriate in view of the nature of the terrain, and the inevitable damage that would occur to the extensive drainage system.
In the event, the autumnal rains were both early and exceptionally copious. And the destruction of the drainage system by shelling was totally catastrophic. Lacking a gravel, or stone, sub-stratum, and bearing a high water table, the entire area, apart from the high ground, was a vast sponge. Accordingly, after the ground had been churned up by shelling, and the drainage network wrecked, it was quickly reduced to an almost impassable morass of glutinous mud and pools of stagnant water: it meant trench warfare without stable trench-works. In effect, it became a battle fought from shell holes whose only lines of communications were a zig-zag of treacherous wooden duck-boards. To stray, or slip, from these fragile pathways incurred a serious risk of drowning in mud and water.
The rationale for, and genesis of, the British offensive in Flanders
So why did the BEF commander, Field Marshal Sir Douglas Haig and his staff, chose to fight a battle there? In response, one is tempted to quote the famous Irishman's reply to a request for directions to a particular village: 'If I were going there, I wouldn't start from here'.
In fact, Haig didn't start his offensive at Passchendaele; it was the fourth immediate objective in his overall objective to deprive the Germans of their Belgian Channel Ports of Ostend and Zeebrugge and to deny the German Navy its submarine bases located there. He considered that at a single stroke, this would curtail the depredations of the German U-boats on British and neutral shipping that, at this stage of the war, was so costly that it threatened the entire British war effort.
The genesis of the 1917 Battle of Passchendaele went back to a crucial strategic decision, earlier that year, made by the German commander in Chief, General Erich von Falkenhayn. After the heavy German losses on the Somme and at Verdun in 1916, Falkenhayn decided to withdraw from the battlefield to a new complex and extensive line of defences; called by the British, the Hindenburg Line. Eventually, this complex of entrenchments, strong points and barbed wire, extended across France and into the ridges of Messines and Passchendaele in Flanders. It was a formidable defence line from which the Germans felt able to repel any Allied advance, and one that allowed them to launch their own offensives at a place and time most suitable to them. Haig's riposte to this dramatic initiative was to plan a tentative offensive in Flanders 'sometime in 1917'.
But the Allies strategic position became even more uncertain as 1917 progressed. There were several causative factors.
- Firstly, primarily as a result of General Robert Nivelle's catastrophic offensive in April 1917 by four French Armies (4th, 5th, 6th and 10th) in the Chemin des Dames Sector, elements of the French Army on the Western Front refused to take offensive action, whilst maintaining an effective defensive posture. Others, in smaller numbers, actually mutinied, refused to take any orders from their officers and NCO's and deserted. Certainly, after the traumas of the Verdun and Chemin des Dames Offensives, through which almost every man in the French Army had passed at some time, this option of collectively deserting the battlefield must have been a very seductive one. (Although this mutinous situation was not apparent at the time to the German commanders, or they chose for their own reasons to ignore it, it presented the Allied commanders with a problem of the highest order). Consequently, the burden of maintaining the pressure on the German Army in both Belgium and France had unequivocally passed to the British until such time as the French Army could re-energised and the Americans arrived in significant numbers with the promised large quantities of munitions and armaments.
- Secondly, there was considerable political pressure on Haig from London over the previously mentioned U-boat threat that was aided by German possession of the Belgian ports.
- Thirdly, there was Haig's ambition, despite opposition from the British Prime Minister, Lloyd George, for a British 'breakthrough' before the American Army became fully effective on the Western Front. Haig knew, as did few others, just how large and significant the American contribution would be in 1918 and thereafter. He feared, unnecessarily as events turned out, that a British led victory on the Western Front would slip from his hands. Also, a breakout to the North and East would finally allow Haig to deploy his beloved cavalry. A largely thwarted ambition that had been nursed since the trench warfare began in late 1914, despite all the evidence that mounted cavalry would be unable to contend with the mechanised warfare of the Western Front.
- And, finally, as the overall strategy and tactics were formulated, there was the small scale, but successful, preparatory action at Messines, in June 1917. This gave indications of how a British-led offensive could be achieved with new tactics and heavy artillery support and with relatively light casualties i.e. 17,000 at Messines.
Accordingly, in May 1917, Haig once again set his Headquarters staff the task of the development of a plan for an offensive in Flanders: an attack overland to meet up with troops at landed by sea at Nieuport on the Belgian coast.
The Third Ypres offensive
The plan that emerged from the British HQ was for the joint Anglo-French offensive out of the Ypres Salient led by General Gough's Fifth Army plus one Corps each of General Plumer's Second Army and General Anthoine's First French Army in support. A total of 12 Divisions were launched along an 18km front east of the town of Ypres. It was preceded on the 31st May 1917 by an unprecedented 10-day preliminary bombardment by 3,000 guns delivering over 4 million shells.
The Germans, alerted by this extraordinarily long bombardment, reacted by deploying their now expert use of defence in depth and, in particular, paid attention to the concentration of their defences on Passchendaele Ridge. These defences left the potential avenues of advance for the British firmly located across the existing and potential treacherous marshlands.
A combination of the destructive effect of the artillery bombardment on the land drainage system, and unexpected torrential rain, quickly produced a churned up landscape of mud, water and the detritus of war. Any movement was inordinately difficult and exhausting for man, beast and machine alike; the anticipated decisive deployment of British tanks was an early casualty.
To add to the horrors inflicted on the Allied troops, on the 4th July 1917 the Germans added Mustard Gas to their armamentarium of war.
On the 16th August, after a few days respite in the weather, another attack was launched, this time in the Langemarck Sector over a four-day period but, again, territorial gains were limited and casualties high.
Lieutenant-General Sir Hubert Gough was effectively removed from command and General Sir Herbert Plumer's and his Second Army took the van, launching a new offensive on 20th September in the Menin Road Sector. It was exceptionally well supported by artillery and mortar fire. Plumer's plan was to make limited objective advances using Fourth Army's General Rawlinson's technique of 'bite and hold'. An advance of around 1,000m was achieved at the cost of 20,000 casualties.
Despite the apparently endless deluge of rain, Haig decided to launch two further attacks on the 26th September and 4th October on Polygon Wood and Broodseine Ridge respectively. A further territorial gain of 1,500m was achieved at the cost of 30,000 more casualties. This gave the British a hold on the on the ridge east of Ypres. It also produced in the British High Command a largely unwarranted sense of optimism that the German defences were crumbling. Haig decided to push on, despite the atrocious conditions, for the final few kilometres that would give him possession of Passchendaele Ridge and open up the way to the prize of the Belgian Channel Ports.
A successful attack was made on the 9th at Poelcappe, but the by now exhausted troops were quickly repulsed by German counterattacks.
The 'push' for Passchendaele Ridge
On the 12th October, at Poelcappe, the First Battle of Passchendale Ridge began. Still the casualty list rose and morale began to dip as the struggle ground remorselessly on. An influx of 12 divisions of German troops, who were diverted en route to the Italian Front, made the progress of the British and Dominion troops even slower and more costly.
Despite advice by his field commanders (both Plumer and Gough made personal representations for a cessation of the offensive) Haig persisted in carrying on the advance, bringing into the fray the Canadian Corps commanded by Lieutenant-General Sir Arthur Currie.
On October 26th and 30th the 3rd Canadian Division continued the advance with 60% casualties and captured the town of Passchendaele.
The Canadians in the town were reinforced by two British Divisions and for five days repulsed repeated German attacks until reinforced by two more Canadian divisions.
Passchendaele Ridge finally fell to the Canadians and the British on the 6th November 1917. By the 10th November the surrounding slopes were also in Allied hands. But the British and Dominion troops were so exhausted that any further advance in Flanders in 1917 was out of the question. Effectively, it also reduced the feasibility of any other large-scale offensive elsewhere - hence the tactical debacle at Cambrai later that month when a shortage of reserves, combined with poor generalship, turned a potentially successful strategic initiative into a poor stalemate.
British, Australian and Canadian casualties for the Third Battle of Ypres totalled around 250,000 (some estimates - e.g. Winston S. Churchill - give totals as high as 400,000) of which 66,000 were killed; many of them top-grade Dominion troops. German losses were nearly double that at around 400,000.
The total area gained in the Third Battles of Ypres was around 80 sq. km of which about a third was captured in the Battles of Passchendaele. Around 4,000 British and Dominion soldiers - equivalent to five infantry battalions - fell for each square kilometre of mud and mire that was wrested from the Germans. It is no coincidence that the largest Commonwealth war cemetery on the world - 12,000 graves and panels on the Memorial to the Missing recording another 34,000 - is located at Tyne Cot, on Passchendaele Ridge. The Menin Gate Memorial that records 55,000 British and Dominion soldiers with no known grave, is located only 10 km away on the outskirts of Ypres.
It may be reasonably conjectured that if the BEF was destined to mutiny or desert on the Western Front, Passchendaele was the point at which it was most likely to have taken place. But it did not mutiny. It was generally accepted by the troops involved that, despite its horrors, the Third Battle of Ypres was more of a victory for the British Army than was the First Battle of the Somme. Irrespective of all suffering that they had endured, this now war-hardened and mature army was destined to achieve even greater things in 1918.
However, the question must be posed of how much better things may have been, if the generals and their planning staff had:
- Carried out a more careful study of the terrain of the proposed battlefield as detailed in their own ordnance maps.
- Made the effort to understand a little more the vagaries of a continental climate and its potential effect on the terrain.
- Appreciated that even small a disruption of the drainage systems of low -lying and reclaimed land could have a highly disproportionate effect on its suitability as a modern battlefield.
- Had the moral courage to cut their losses once it became obvious to all concerned, that to struggle on in the increasingly atrocious conditions with enormous casualties was a strategic error of the first order.
In the final analysis, perhaps the Irishman was right; they shouldn't have started from there!