Introduction
Once the war on the Western Front in 1914 went to ground, and became a nearly 500 mile long struggle across No Man's Land, each of the belligerent High Commands had to develop a strategy of defence and offence almost from scratch. Of course, the precedents had been set in the American Civil War (1861-66) and the Russo-Japanese War (1904-05). In both these conflicts there had been phases where the infantry had taken to the trenches. However, neither of the High Commands of the Great Powers nor the Allies had given much serious thought to this as a possible feature of the long anticipated European War. Quite unexpectedly, the extension of the trench systems had occurred almost overnight along the whole Western Front from the North Sea to the Swiss border. And the generals had no ready-made plan how to deal with this situation.
French perspective
For the French, there was little equivocation concerning what action should be taken; regardless of this novel situation. The French philosophy of war had become set in stone after the 1870 Franco-Prussian War. It postulated that in any European War, invasion would come from Germany, which continually grew in strength in population, as well as economic and military power. Accordingly, a double line of supposedly invulnerable sunken forts were built along an almost uninterrupted line that paralleled the Franco-German border from Switzerland to Belgium. Also, over the years prior to 1914, and under the patronage of Col. Louis de Grandmaison, Chief of Operations for the General Staff, the French Army adopted the dogma that at all times there should be a stance of immediate counter-attack the so called - 'l'attaque à outrance'. No offensive action would be left unanswered; whatever the cost. Gaps were deliberately left in the French fortified defence line as potential traps where the invading Germans could be encircled, and annihilated, by ruthless French offensive action.
This attitude, allowed the Great War French Army, at great cost in men and matériel, to a launch a whole series of offensives against the German invaders with great valour and élan (dash). Prominent among which were the successful staunching of the German advance in the autumn of 1914, the hammering of the Germans to an exhausted draw at Verdun and the valiant, but futile, pursuit of the ill-founded, grandiose objectives of the Nivelle Offensive in 1917.
Unfortunately, in the process of this dogma of attaque à outrance, the morale and élan of the French Army was seriously compromised and significant elements of it mutinied in May/June 1917. It required the imposition by General Henri-Phillippe Benoni Omer Joseph Pétain of a more rationale policy of improved conditions of service for the soldiers, and a less aggressive operational strategy, to restore order and competence. Nonetheless, these earlier excesses of the French generals left the entire French Army in a state of psychological and physical debilitation from which it never really recovered; as demonstrated in the fiasco of the Fall of France in 1940 in the Second World War.
German perspective
The Germans, on the other hand, had lost the initiative in 1914 with the failure of the fatally modified Schlieffen Plan. The vaunted 'northern wing' of the advance had been weakened by the Chief of the General Staff, General Helmuth Johannes Lugwig von Molkte, and failed to achieve its final objectives of the capture of Paris and encirclement of the French Army. At this stage, in late 1914, the Germans were well installed in both France and Belgium, with not a single Allied soldier lodged on German soil. The Germans decided to dig in and defend the territory they occupied, confident that neither the French nor the British could wrest it from them in the foreseeable future.
For the Germany Army, there were several major tactical errors. After the aforementioned failure of the Schlieffen Plan, came Verdun, where General Erich von Falkenhayn attempted to 'Bleed the French Army white'. In the process he wreaked almost as many casualties on his own army as he did the French. Finally, there was the ultimately disastrous launching of the Kaiserschlacht (The Emperor's Battle) on the 21st March 1918.
Between times, the German devoted much thought and time to the development of innovative techniques of trench warfare.
From 1915 onwards, the tactic of 'Defence in depth' became the backbone of German defensive strategy. This utilised the tactic of drawing an exhausted enemy deep behind the lightly manned front lines into a shelter-less 'Killing Zone' that was heavily strafed by machine-gun and artillery fire.
In September 1917, a new German offensive tactic of 'Infiltration' was first used on the Eastern Front 1917, and elite Storm[trooper] Battalions were formed to bring this kind of trench warfare to the Western Front. It involved laying down a short 'hurricane' artillery barrage, followed up by the rapid deployment of highly trained and exceptionally well equipped troops to by-pass strong points and attack the rear areas, and the artillery, putting the defenders into disarray. The bulk of the infantry would then isolate and mop up the by-passed strong points. In this way significant gains in territory could be achieved in a relatively short period. However, the limits of penetration still remained dependent upon problems arising from supply and transportation over long distances, as the German found to their cost in the later stages of the Kaiserschlacht in the Spring of 1918.
These new German strategies, plus their superior defensive techniques, and brilliantly constructed fortifications, generally served them well until the final stages of the war in 1918.
Consequently, with the odd exception (e.g. Verdun), throughout the war the comparable casualty rolls were always strongly in the Germans' favour. That is, the Germans generally fought better planned and executed campaigns, and a less expensive war.
British response
The initial British response to trench warfare in 1914-15 was less clear cut and rather confused. It was generally oriented to a policy of offensive action by attempting to create a breech in the German defense line with the use of artillery and infantry that would allow a follow-through intervention by the cavalry. Once the German defence-line was reduced to an appropriate level, it was intended that the cavalry would then be free to charge through and take the war into the open country behind the German lines (e.g. the objectives of the towns of Lille, at the Battle of Neuve Chapelle in 1915, and Bapaume, at the First Battle of the Somme in 1916).
With the dismissal, in December 1915, of General Sir John Denton Pinkstone French, as Chief of the British Expeditionary Force (BEF), and his replacement by General Sir Douglas Haig (a cavalry man), the British effort became formally committed to what Haig persistently called 'The Breakthrough'.
'The Breakthrough' was basically the same British tactic as described earlier, but on a much larger scale, i.e. the massed artillery and infantry would be concentrated on specific and limited area of the enemy front, with the cavalry, poised in the rear area, ever ready for an opportunity to advance.
Throughout the entire war, the British cavalry on the Western Front was never provided with the required degree of opportunity. And, the huge commitment the British Army made throughout the war in maintaining its cavalry force of up to five divisions, was never repaid by any really worthwhile level of success; other than, perhaps, when some of the units were converted to other cadres such as machine-gunners and infantry
Even before General Haig began his dogged pursuit of his policy of 'The Breakthrough', other influential minds had been searching for means to break the stalemate in the trenches. Prominent among these was three options: the introduction of an armoured vehicle (the so-called 'Tank'); a more restrictive, but intensive, offensive system known as 'Bite and Hold' and a closer co-ordination between the infantry and the artillery. This latter idea eventually evolved into the concept of a centralised artillery fire-plan which itself included 'The Creeping Barrage'.
The advent of the tank
The development of a tracked armoured vehicle for the Western Front was first proposed, in December 1914 by Col. Maurice Hankey, Secretary of the Committee for Imperial Defence, based on earlier suggestions by Mr. L. E. Mole and Lt.-Col. Ernest Swinton. Hankey's memorandum was noted by the First Lord of the Admiralty, Mr. Winston Spencer Churchill, in February 1915. It was he, Churchill, who got the British Government to approve a secret development project for what came to be code-named 'The Tank'. Significantly, in the later stages of the development process, General Sir Douglas Haig, C-in-C, BEF, also became a firm supporter of the project.
It was thought that if sufficient numbers of these armoured tracked vehicles could be concentrated on a suitable area of the front line, the infantry could be led forward, and sheltered by them, as they breached the barbed wire, crossed the enemy trenches and dealt with the enemy strong-points. Unfortunately, at first, this concept was not properly followed, and success only came in the 1917 Cambrai Offensive (381 tanks deployed) and the battles in mid- and late 1918 (up to 604 Allied tanks deployed). The full war winning potential of these vehicles was clearly demonstrated, but never fully realised in the Great War.
New concept
The 'Bite and Hold' concept gradually emerged in late 1915 from the staff of General Sir Henry Rawlinson commander of the Fourth Army of the BEF in France. In principle it was similar to the later German 'infiltration' tactic but much more limited in scope. It used a concentrated barrage of artillery - several hundreds of pound of shells per yard of front - to wreck the German trenches and fortifications. This was followed up by a rapid advance by the infantry, under an umbrella of shellfire (see 'Creeping Barrage' below), to seize a small sector of the defences (the 'Bite') and hold it. Under the shelter of further precision shelling, the British reserves could then be brought up to repel the inevitable German counter attack. In this way, progressive chunks of the German defences could be eroded away leading to an eventual 'Breakthrough'. After several disastrous attempts at this tactic, to some extent comprised by Haig's insistence of a more extensive attack (e.g. The First Battle of the Somme), limited success in 'Bite and Hold' was achieved at Vimy Ridge, Arras and Messines in 1917. This was ultimately followed by more general success in the famous final '100 Day Offensive', in mid-1918, where sequential 'Bite and Hold' attacks proved to be highly effective.
The concept of the 'Creeping Barrage' was for the infantry to advance towards the enemy closely behind an artillery barrage that moved forward at a precisely pre-determined rate (e.g. 50 yards/metres per minute). Thus the enemy could not leave their shelters until the advancing troops were almost literally upon them. The idea is generally attributed to the British, namely General Sir Henry Rawlinson of the BEF's Fourth Army. Fourth Army first tried the 'creeping barrage' concept on Day 1 (1st July 1916) of the First Battle of the Somme, with only limited success, due to then usual lack of co-ordination and communication. Thereafter, it was to become the standard British artillery/infantry procedure in all the subsequent offensives; with generally increasing success whenever it was properly planned and executed. It was also adopted by all the other belligerent nations.
Conclusions
Of all the learning curves imposed on the belligerent nations by the imperatives of trench warfare, it was those achieved by British and Commonwealth Army that were, in the end, decisive. Supported by the added numerical strength and the 'vigourous muscle' of the Americans, Britain and its Commonwealth armies, with their stricken but still active French allies, were finally able to prevail under basically the same leadership of Haig and Rawlinson that existed in the dark days of 1915. The obviously superior German methodology and technology of 'total war' had eventually been overcome and the Germans lost the war.
