Trench warfare: Encyclopedia II - Trench warfare - Implementation

Trench warfare - Implementation

Although firearms technology and the conscript army dramatically changed the nature of warfare, most armies were completely unaware of the implications of these changes and unprepared for their consequences. At the start of World War I, most armies prepared for a brief war whose strategy and tactics would have been familiar to Napoleon.

However, as war broke out, German and Allied (mostly French and British) forces soon learned that with modern weapons even a shallow scrape in the soil could be defended by a handful of infantry. To attack frontally was to court crippling losses, so an outflanking operation was essential. After the Battle of the Aisne in September 1914, an extended series of attempted outflankings, and matching extensions to the fortified defensive lines, soon saw the celebrated "race to the sea"—the German and Allied armies dug what was essentially a single pair of trenches from the Swiss border in the south to the North Sea coast of Belgium. Trench warfare prevailed on the Western Front from September 16, 1914, until the Germans launched their "Spring Offensive", Operation Michael, on March 21, 1918.

On the Western Front, the small improvised trenches of the first few months rapidly grew deeper and more complex, gradually becoming vast areas of interlocking defensive works. The space between the opposing trenches was referred to as "no man's land" and varied in distance depending on the battlefield. On the Western Front it was typically between 100 and 300 yards, though only 30 yards on Vimy Ridge. After the German withdrawal to the Hindenburg line in March 1917, it stretched to over a kilometre in places. At the infamous "Quinn's Post" in the cramped confines of the Anzac battlefield at Gallipoli, the opposing trenches were only 15 metres apart and a bombing war was waged there incessantly. On the Eastern Front and in the Middle East, the areas to be covered were so vast, and the distances from the factories that supplied shells, bullets, concrete and barbed wire so great, that trench warfare in the European style often did not eventuate.

In the Alps the trench warfare even stretched into the 3rd dimension, on vertical slopes and deep into the mountains, up to heights of 3900 meters above sea level (the Ortler had an artillery position on its summit near the front line). The trench-line management and trench profiles had to be adapted to the rough terrain, hard rock and the harsh weather conditions. Many trench systems were constructed within glaciers like the Adamello-Presanella group or the famous city below the ice on the Marmolada in the Dolomites.

Trench warfare - Defensive system

Very early in the war the British defensive doctrine suggested a main trench system of three parallel lines with each line connected by communications trenches. The point at which a communications trench intersected the front trench was of critical importance and was usually heavily fortified. The front trench was lightly garrisoned and typically only occupied in force during "stand to" at dawn and dusk. Between 70 and 100 yards behind the front trench was located the support (or "travel") trench to which the garrison would retreat when the front trench was bombarded. Between 300 and 500 yards further to the rear was located the third reserve trench, where the reserve troops could amass for a counter-attack if the front trenches were captured. This defensive layout was soon rendered obsolete as the power of the artillery grew; however, in certain sectors of the front, the support trench was maintained as a decoy to attract the enemy bombardment away from the front and reserve lines. Fires were lit in the support line to make it appear inhabited, and any damage due to shellfire was immediately repaired.

Temporary trenches were also built. When a major attack was planned, assembly trenches would be dug near the front trench. These were used to provide a sheltered place for the waves of attacking troops who would follow the first waves leaving from the front trench. "Saps" were temporary, unmanned, often dead-end utility trenches dug out into no man's land. They fulfilled a variety of purposes such as connecting the front trench to a listening post close to the enemy wire or providing an advanced "jumping-off" line for a surprise attack.

When one side's front line bulged towards the opposition, a "salient" was formed. The concave trench line facing the salient was called a "re-entrant". Large salients were perilous for their occupants because they could be assailed from three sides.

Behind the front system of trenches there were usually at least two more partially prepared trench systems, kilometres to the rear, ready to be occupied in the event of a retreat. The Germans often prepared multiple redundant trench systems; in 1916 their Somme front featured two complete trench systems, one kilometre apart, with a third partially complete system a further kilometre behind. This duplication made a decisive breakthrough virtually impossible. In the event that a section of the first trench system was captured, a "switch" trench would be dug to connect the second trench system to the still-held section of the first.

The Germans made something of a science out of designing and constructing defensive works. They used reinforced concrete to construct deep, shell-proof, ventilated dugouts as well as strategic strongpoints. They were more willing than their opponents to make a strategic withdrawal to a superior prepared defensive position. They were also the first to apply the concept "defence in depth", where the front-line zone was hundreds of yards deep and contained a series of redoubts rather than a continuous trench. Each redoubt could provide supporting fire to its neighbours, and while the attackers had freedom of movement between the redoubts, they would be subjected to withering enfilade fire. The British eventually adopted a similar approach, but it was incompletely implemented when the Germans launched the 1918 "Spring Offensive" and proved disastrously ineffective.

Trench warfare - Trench construction

Trenches were never straight but were dug in a square-toothed pattern that broke the line into bays connected by traverses. This meant that a soldier could never see more than 10 metres or so along the trench. Consequently, the entire trench could not be enfiladed if the enemy gained access at one point or if a bomb or shell landed in the trench; the fragmentation (often incorrectly called shrapnel) could not travel far. The side of the trench facing the enemy was called the parapet and had a fire step. The rear of the trench was called the parados. The parados protected the soldier's back from fragmentation from shells falling behind the trench. If the enemy captured the trench, then the parados would become their "parapet". The sides of the trench were revetted with sandbags, wooden frames and wire mesh. The floor of the trench was usually covered by wooden duckboards.

Dugouts of varying degrees of luxury would be built in the rear of the support trench. British dugouts were usually 8 to 16 feet deep, whereas German dugouts were typically much deeper, usually a minimum of 12 feet deep and sometimes dug 3 stories down with concrete staircases to reach the upper levels.

To allow a soldier to see out of the trench without exposing his head, a loophole would be built into the parapet. A loophole might simply be a gap in the sandbags or it might be fitted with a steel plate. German snipers used armour-piercing bullets that allowed them to penetrate loopholes. The other means to see over the parapet was the trench periscope—in its simplest form, just a stick with two angled pieces of mirror at the top and bottom. In the Anzac trenches at Gallipoli where the Turks held the high ground, the periscope rifle was developed to enable the Australians and New Zealanders to snipe at the enemy without exposing themselves over the parapet.

There were three standard ways to dig a trench: entrenching, sapping and tunnelling. Entrenching, where a man would stand on the surface and dig downwards, was most efficient as it allowed a digging party to dig the length of the trench simultaneously. However, entrenching left the diggers exposed above ground and hence could only be carried out when free of observation, such as in a rear area or at night. Sapping involved extending the trench by digging away at the end face. The diggers were not exposed, but only one or two men could work on the trench at a time. Tunnelling was like sapping except that a "roof" of soil was left in place while the trench line was established and then removed when the trench was ready to be occupied. The guidelines for British trench construction stated that it would take 450 men 6 hours (at night) to complete 250 metres of a front-line trench system. Thereafter the trench would require constant maintenance to prevent deterioration caused by weather or shelling.

The battlefield of Flanders, which saw some of the worst fighting, presented numerous problems for the practice of trench warfare, especially for the British, who were often compelled to occupy the low ground. In most places, the water table was only a metre or so below the surface, meaning that any trench dug in the ground would quickly flood. Consequently, many "trenches" in Flanders were actually above ground and constructed from massive breastworks of sandbags (actually filled with clay). Initially, both the parapet and parados of the trench were built in this way, but a later technique was to dispense with the parados for much of the trench line, thus exposing the rear of the trench to fire from the reserve line in case the front was breached.

Trench warfare - Trench geography

The confined, static and subterranean nature of trench warfare resulted in it developing its own peculiar form of geography. In the forward zone, the conventional transport infrastructure of roads and rail were replaced by the network of trenches and light tramways. The critical advantage that could be gained by holding the high ground meant that minor hills and ridges gained enormous significance. Many slight hills and valleys were so subtle as to have been nameless until the front line encroached upon them. Some hills were named for their height in metres, such as Hill 60. A farmhouse, windmill, quarry or copse of trees would become the focus of a determined struggle simply because it was the largest identifiable feature. However, it would not take the artillery long to obliterate it, so that thereafter it became just a name on a map.

Battlefield features could be given a descriptive name ("Polygon Wood" near Ypres or "Lone Pine"), a whimsical name ("Sausage Valley" and "Mash Valley" on the Somme), a unit name ("Inniskilling Inch" at Helles named for the Royal Inniskilling Fusiliers) or the name of a soldier ("Monash Valley" at Anzac named after General John Monash). Prefixing a feature with "Dead Man's" was also popular for obvious reasons, such as "Dead Man's Road" leading in to Pozières, "Dead Man's Ridge" at Anzac or "Le Mort Homme" at Verdun. There were numerous trench networks named "The Chessboard" or "The Gridiron" because of the pattern they described. For the Australians at Mouquet Farm, the advances were so short and the terrain so featureless that they were reduced to naming their objectives as "points" on the map, such as "Point 81" and "Point 55".

Enemy trenches, which would become objectives in an attack, needed to be named as well. Many were named for some observed event such as "German Officers' Trench" at Anzac (where a couple of German officers were sighted) or "Ration Trench" on the Somme (where German ration-carrying parties were sighted). The British gave an alcoholic flavour to the German trenches in front of Ginchy: "Beer Trench", "Bitter Trench", "Hop Trench", "Ale Alley" and "Pilsen Trench". Other objectives were named according to their role in the trench system such as the "Switch Trench" and "Intermediate Trench" on the Somme.

Some sections of the British trench system read like a Monopoly board, with names such as "Park Lane" and "Bond Street". British regular divisions habitually named their trenches after units, which resulted in names such as "Munster Alley" (Royal Munster Fusiliers), "Black Watch Alley" (Black Watch Regiment) and "Border Barricade" (Border Regiment). The Anzacs tended to name features after soldiers ("Plugge's Plateau", "Walker's Ridge", "Quinn's Post", "Johnston's Jolly", "Russell's Top", "Brind's Road" and so forth).

Adapted from the Wikipedia article "Implementation", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki