The Western Front became static in the opening months of the war. Neither the Allied nor German armies could breach the other’s lines and therefore dug themselves into trenches, with the hostile expanse of No-Man’s Land between them. No-Man’s Land was only a few metres wide in some places along the Front, extending in places to a width of over a kilometre.

The Front was not one unbroken line of trench but a maze of trenches and trench lines, each with different uses. From No-Man’s Land to the rear, there were three main trench lines: the front line (or “fire”) trench, the support trench and the reserve trench. The front line trench was the main fighting trench and was the most heavily manned and defended. It was from here that attacks were mounted and enemy attacks countered. Behind this was the support trench, designed as a fall-back position in the event of the front line trench being overrun by the enemy and to shelter support troops behind the front line. Behind this was the reserve trench where troops in reserve were stationed before being sent further forward. Connecting each trench line and running perpendicular to them were communication trenches. These provided safe passage for men moving between the three trench lines, and to and from the rear areas. Trenches were not usually dug in a straight line, but in a zigzag pattern to reduce casualties when a shell burst in the trench, and to reduce the risk of enfilade fire from an enemy who invaded the trench.

The trenches were protected from enemy intrusion by rolls of barbed wire, which could extend from the front line trench up to 50 metres into No Man’s Land.

The Germans, having captured strategically important positions before digging in, almost always dug their trenches at the top of slopes and ridges, and nearly always occupied the high ground. Their trenches were generally more strongly constructed than the British and French equivalents and utilised deep dug-outs as shelter for their men.

As a further defensive measure, both sides constructed concrete emplacements for protection against shellfire. The Germans in particular employed a large number of well-placed concrete “pillboxes” as shelter for machine-gun crews. Machine guns could fire on advancing infantry through loop holes in the pillbox wall or from the top or sides of the emplacement. Impervious to shellfire, these well-defended fortifications could only be captured by infantry assault.

Far behind the front line, both sides employed artillery to constantly shell their enemy’s trenches and rear areas. Early in the war the Germans had a larger supply of heavy artillery guns, but the imbalance had reversed by 1917. There were three types of artillery shell: High Explosive (HE) shells burst on impact with the ground, creating a large explosion and sending jagged fragments of their iron casing hurtling in all directions. HE shells were designed to destroy trenches, roads and buildings and kill or injure troops. Shrapnel shells were timed to explode in mid-air at a predetermined height above the ground, the explosion releasing a hail of small lead balls (“shrapnel”) in a shotgun effect. These were used primarily against infantry, with devastating effect. Gas shells were used to deposit poisonous gas in the enemy’s lines and released the toxic substance upon bursting. (As an aside, people are often confused by the meaning of the word “shrapnel”. Recently the term has been popularly applied to any fragment of an exploded shell. Technically this is not correct – only lead balls from a shrapnel shell should be described as “shrapnel”.)

At the front line, the trenches were defended by machine guns spaced at intervals along the trench. The Germans had readily embraced this new weapon, and issued large quantities to their army from the start of the war. The British were not convinced the machine gun played a valuable role in modern warfare, and described it as a “weapon of opportunity”. As such, the British were badly under-equipped with machine guns in the war’s early stages. The value of the machine gun was not only in it’s rapid rate of fire – both the German Maxim gun and the British Vickers fired at a rate of about 600 rounds per minute – but in its accuracy. A properly sighted machine gun mounted on its heavy base could pour fire across the top of a trench or into a gap in the barbed wire with minimal input from its operator. Its accuracy did not rely on the careful aim of the firer, and was not diminished even if the firer was in a panic in the face of an enemy attack. A well positioned machine gun could disrupt the advance of an entire enemy battalion (over 1000 men).

Individual soldiers relied on three primary weapons for personal defence: the rifle, the bayonet and the grenade.

The rifle was the infantryman’s constant companion. This was the first war to employ rifles which were both accurate and had a high rate of fire - both the British Lee-Enfield and the German Mauser were capable of producing 15 well aimed shots per minute in the hands of a competent firer. Although sturdy in design, the rifle required constant attention to keep it performing at its best – dirt and mud could constrict the rifle’s action or obstruct the barrel, sending shots wide. Every infantryman had a personal investment in keeping his rifle clean and well maintained. 

The bayonet was one of the war’s more sinister weapons. Fixed to a rifle, it gave the infantryman an effective close-quarters weapon. It has been said that, during the First World War, no soldier was ever bayoneted who didn’t have his hands up first, but soldiers’ accounts contradict this. The bayonet was the weapon of choice in close quarter fighting.

The grenade (or “bomb”) first appeared in its modern form during the First World War. In the hands of a competent thrower the grenade was an extremely effective weapon. Both sides employed a range of grenades during the war, but the German stick grenade and the British Mills bomb were the most commonly used. Both could be thrown a good distance and caused much destruction when exploding amongst enemy troops. Specially trained men were employed as “bomb throwers” but all infantryman generally carried a few grenades each into battle. As well as being thrown by hand, grenades could be fired from a cup-like mechanism on a rifle, greatly extending their range.

Other weapons were also employed during the war including trench mortars (which fired an explosive projectile over a short to medium distance), light machine guns (such as the American Lewis gun, used by the British, and the German Maxim 08/15) which were more manoeuvrable and required less operators than a standard machine gun, flame-throwers (used predominantly by the Germans late in the war) and clubs and knives (used in close-quarter trench fighting). 

Poison gas was first used in 1915 and was originally dispensed from drums and allowed to drift over the enemy lines. This system relied on a favourable wind, of course, and was abandoned as soon as more practical methods were devised. These included the gas shell, which dispensed the gas upon exploding and the “gas projector”, a simple mortar that launched a gas cylinder into the enemy’s lines which broke open on impact, dispensing the gas. Infantry carried gas masks close at hand which provided some protection from gas attacks. Throughout the war gas remained a terrifying weapon.

Elementary tanks were invented by the British during the First World War and first appeared on the Somme in 1916. Although terrifying to the German defenders, these lumbering beasts were slow and unreliable. By 1918 several improvements had been made, and the tanks became a valuable asset during the allied advance to victory. The Germans produced a tank of their own late in the war and, although it was a fearsome weapon, it was never produced in numbers great enough to have any real influence on the war.