At the turn of the twentieth century railways dominated land transport. Motor vehicles had yet to seriously threaten the railways, except for local traffic, while aviation was at an embryonic stage. Consequently the main belligerent nations of Europe built their plans for mobilising and supporting their armies in war primarily around railways. Each nation had developed very sophisticated schedules for concentrating troops and equipment at key depots and then despatching the forces rapidly to designated positions on their frontiers.
Nowhere was the planning more developed than in Germany and France. Germany's 'Schlieffen Plan' provided for concentrating forces by rail rapidly along both the eastern and western boundaries. It was expected that the Russian Army would be slow to mobilise, so the strategy was to sweep rapidly through Belgium and Luxembourg, invade northern France and encircle around the north and west of Paris. Following a French surrender, expected within six weeks, the forces could then face the Russians.
In the event, strong Belgian resistance, including extensive demolition of railway infrastructure, delayed the advance and the use of the network to supply German forces. Even a month after the occupation of Belgium, barely 15 per cent of the railway network was operating despite 26,000 workers being drafted in.
The rapidly advancing German troops far outran their supply lines once they entered France. They were soon up to 80 miles ahead of their nearest railhead, and horse-drawn transport could not adequately bridge the gap. The increasingly exhausted German troops were short of food and ammunition, and also faced stiffening resistance as the French used their well-developed rail network around Paris to assemble a new army to protect the capital. Meanwhile British forces were rushed across the Channel and deployed with the French and Belgian forces. The German advance ground to a halt. This theme - of the momentum of an initially successful advance faltering as supply lines were outrun, while defending forces were rapidly concentrated to fill the breech - was to be replayed many times during the next four years.
The Entente and the Central Powers agreed upon one expectation at the outset: that there would be a rapid, offensive war which would be over quickly. They were wrong. By Christmas 1914, defensive lines of trenches stretched from the Channel coast to the Swiss border.
Maintaining these huge forces in the field - up to 2 million men were serving on the Western Front - required vast amounts of supplies. Every bullet, blanket, bandage, artillery battery or tin of bully beef had to be manufactured and transported where and when it was required. By 1918 each Division of about 12,000 men needed about 1,000 tons of supplies every day - equivalent to two supply trains each of 50 wagons. When an offensive was being planned, even larger quantities of material had to be concentrated in preparation for the operations that might last for months.
Railways were the only way of shifting this volume of material overland and a very sophisticated transportation and supply system was developed, especially after a major reorganisation in 1916. For the British the challenge was complicated by the English Channel. War material had to be railed to a Channel port and, until special ferries were built to carry wagons, loaded onto a ferry, reloaded onto a French train or barges and carried forward to the main supply dumps behind the British lines.
Getting close to the front was the relatively easy part of the process. The problems really began about 7 miles behind the front. Anywhere beyond this point was potentially within range of the devastating effects of long distance artillery shelling. Consequently the main supply dumps and railway yards had to be established before this danger zone had been reached.
The next problem was how to bridge the gap between the supply dumps and the soldiers who needed the supplies - and the problems got more and more difficult the closer supplies were moved towards the front lines. This distance was too long to be bridged effectively with horse-drawn vehicles, because horses could not manage a daily round trip of this length.
The French and Germans had a ready solution for the first part of this journey because they had recognised before the war that there would be an important role for 60cm gauge light railway systems. These were like model train sets with light, narrow gauge sections of railway line that could be easily laid on the ground and relocated when they were needed elsewhere. They quickly established networks that led from the main supply dumps to the artillery batteries and then further forward to smaller supply dumps and refilling points from which the front lines could be served.
The British, however, planned for a more mobile war and had decided to rely primarily on motor transport. Over 1,000 civilian lorries and over 300 buses were requisitioned at the outbreak of hostilities and were hurriedly moved across the Channel. The owners had been encouraged by a financial subsidy to purchase vehicles that met a War Department specification, a condition of which was that the vehicles could be requisitioned. These were only a temporary stopgap - although some vehicles such as London buses remained in service throughout the war - and thousands more vehicles were ordered from manufacturers in Britain and increasingly the USA. In the meantime, a heavy reliance had to be placed on far less efficient horse-drawn transport. The fodder for the horses alone took up more transportation capacity than food and ammunition for the men.
The inadequacy of motor transport was cruelly exposed during the Somme campaign from July 1916 onwards. The combination of heavy rainfall, inadequately built roads and the pounding caused by large numbers of heavy lorries on narrow, solid-rubber tyres caused the supply lines literally to bog down in the mud. The British artillery was to fire nearly 28 million shells during the Somme battles, but increasingly the 20,000 tonnes of supplies required daily to support an offensive on a front of about 12 miles could not be distributed adequately.
Belatedly the British also decided to embark upon the rapid development of light railway systems. However, they found to their consternation that the main British railway manufacturers already had a huge backlog of French orders. Only American industry could supply material in large quantities at such short notice to augment the limited British manufacturing capacity.
By late 1916 construction of lines was under way, and between January and September 1917 the average tonnage conveyed weekly on light railways operated by British and Dominion forces expanded from barely 10,000 tonnes to more than 200,000 tonnes. The network was to grow to some 2,000 miles of track.
Light railways could bridge part of the gap but also became vulnerable to enemy artillery and small arms fire as they got closer to the front. Consequently, smaller dumps were established at road-heads from which horse and mule transport collected material. Often the final leg had to be carried out by the soldiers themselves carrying the food, water and other supplies to the front lines. This relentless challenge to maintain the flow of supplies forward from the supply dumps had to be undertaken largely at night to minimise the risk from harassing fire.
By early 1917 these increasingly complex transportation networks - supported by a specially created Labour Corps which included tens of thousands of men recruited from China, Egypt, India and other Empire countries - were capable of supporting defensive lines almost indefinitely. They also developed the capacity to support the concentration of forces and supplies sufficient to unleash a blow that could shatter the opposing lines.
But even this revealed a further problem. As the troops advanced, supplies and reinforcements had to be brought forward across the shattered landscape of the battlefield where roads and railways had been obliterated. Despite the best efforts, it took time to build new lines of communication. Only then could artillery and infantry be moved forward with adequate supplies. This slowed the rate of advance, while the retreating troops fell back onto their supply lines and were augmented by reinforcements brought in by road and rail to stem the tide. At the end of offensive and counter-offensive the lines generally stabilised close to where they had begun.
It was only in 1918 that these supply problems were sufficiently overcome to allow offensives to be sustained. So crucial was transportation that in the last months of the war, despite a shortage of front line soldiers, men with railway experience were being transferred from infantry units to railway operating companies. Ultimately the momentum of the advances from August onwards that precipitated the end of the war was able to be supported adequately. But it was a close-run thing, with the Fourth Army operating 50 miles ahead of the only reliable railhead when the Armistice came into force.
On the home front the possible impacts of a European war had been foreseen long before 1914, and plans to put the British railways on a war footing had been prepared. On 5 August 1914, the government took over the railways and vested control in a Railway Executive Committee, which included the managers of the biggest railway companies. The railways met the first test, of moving nearly 120,000 men and equipment in 670 special trains to the main embarkation port of Southampton by the end of August. In the following months the main supply links to France through the channel ports were reinforced with judicious enhancements to the network.
The railways rapidly faced several major challenges. Just as the demand for transport increased, many able-bodied men volunteered for military service. Increasingly, the gap was filled by recruiting women to take on numerous roles that had previously been barred to them.
There was also a much greater demand on the available locomotives, rolling stock and infrastructure. This became much more pressing from 1916, when large amounts of equipment were transported across the Channel in response to appeals from the French authorities to meet chronic shortages. At the same time British industry, including major railway workshops, had been reorganised to massively increase the production of armaments. However, it was very evident that new equipment would be needed urgently and a simple, rugged freight locomotive previously designed for the Great Central Railway was selected in 1917 and 521 engines were built.
Although the railways were heavily focussed on traffic to and from the Channel ports, they also had to respond to many other demands. One of these arose when the supply of steam coal from the Welsh mines for the Grand Fleet based at Scapa Flow was threatened by submarine attacks on coastal shipping. Coal suddenly had to be railed over 700 miles up to the northern tip of Scotland, largely along a single track route that had never been designed for heavy freight traffic. By the end of the war over 5 million tonnes of coal had been carried on 'Jellicoe Specials', but the congestion caused was a factor in Britain's worst ever rail disaster at Quintinshill in May 1915 where 227 people died.
Road transport also experienced huge impacts from the war, starting with the sudden disappearance of requisitioned buses, lorries and horses. The motor vehicle manufacturing industry increased production but it was a slow process because the industry was generally small and fragmented. One of the best-prepared companies was AEC, a subsidiary of the companies operating much of London's bus, tram and underground services. It was able to expand its pre-war bus production lines and they alone produced over 10,000 lorries during the war. Although many other manufacturers increased their output, the large number of different lorry designs remained a major problem, especially complicating maintenance and repairs.
While the Western Front was relatively close to the major manufacturing centres of Europe, and was supported by extensive road and rail networks, the situation was very different on other fronts. The Gallipoli campaign could only be sustained by shipping supplies through the Mediterranean and using lighters and small vessels to take them ashore. There, the foothold on Turkish territory was so small that horse transport and men undertook most of the transportation forward. The Turkish forces also relied heavily on shipping across the Sea of Marmara to supply their forces. For both sides submarine warfare and mines posed a serious threat to supply lines.
The Salonika campaign also relied heavily on lengthy supply lines by sea from Britain and France. As the submarine threat grew, an alternative, largely overland route was developed. Supplies from Britain were routed through the port of Cherbourg and trains then ran across France and Italy to Taranto where ships carried them across the Aegean to the small port of Itea. A fleet of lorries provided the next link across the rugged mountains of central Greece to Bralo, where the final stage was completed by standard gauge rail to Salonika. Fighting a campaign north of Salonika, initially to support Serbia, presented many challenges that were different to the Western Front. To support a 250-mile-long front, largely through remote mountainous terrain or along mosquito-infested river valleys, there were only a couple of existing railways and virtually no metalled roads. A single road, to Seres, supplied virtually half the British front, and collapsed rapidly under the traffic.
A huge construction and maintenance programme to improve communications was undertaken, including large numbers of civilian labourers and prisoners of war. By 1918 the labour force included more than 16,000 Greek men, 3,700 Greek women and 4,500 Turkish POWs. Entire new railways were built including a light railway nearly 60 miles long to support troops in the lower reaches of the Struma River valley. However, the terrain near the front was often impassable for wheeled vehicles and so pack animals were used extensively.
The end of the Salonika campaign came suddenly, after several years of stalemate. A surprise French and Serbian attack broke through the Bulgarian lines high in the mountains and pushed on to the Vardar River valley, severing the main railway line supplying the central and eastern half of the Bulgarian front. While the Bulgarians were forced to abandon this part of the front, a daring mounted force pushed northwards to Skopje and also cut the supply routes to the western part of the front, precipitating the end of the war in this theatre.
When Turkey entered the war on the side of the Central Powers, its declining Ottoman Empire still extended through Palestine and southwards along the eastern shores of the Red Sea, including much of modern day Iraq and reaching the Persian Gulf. Egypt, although nominally part of the Ottoman Empire, was under British control to protect the Suez Canal, which provided a vital link to its Empire in India, Asia and much of Africa.
Initial Turkish attempts in 1915 to invade Egypt from Palestine and cut the canal were repulsed. British and Dominion forces then pushed Turkish forces eastwards, back across the Sinai desert, with the advance almost entirely dictated by the rate of progress in building hundreds of miles of roads, railways and a water pipeline across the desert. However, there was still a major role for animals in distributing supplies, with the Egyptian Camel Transport Corps having a crucial function.
Once Gaza and Beersheba had been taken, the existing Turkish narrow gauge railways were converted to standard gauge to support the advance towards Damascus. The offensive was assisted greatly by a guerrilla campaign waged mainly by Arab irregular forces against the Turkish Hedjaz railway. This line had been built shortly before the war from Damascus over 800 miles southwards to Medina, largely to strengthen Ottoman control of the region. Thousands of Ottoman soldiers were deployed to defend the railway from the increasingly effective sabotage. By the final months of the war, as General Allenby advanced towards Damascus, more Ottoman soldiers were strung out in strongpoints along the Hedjaz railway than were trying unsuccessfully to stem his advance.
Meanwhile, further to the east, a campaign was fought along the valleys of the Tigris and Euphrates Rivers. Oil was vital to Britain for fuelling its most powerful warships, as well as for motor transport. British forces therefore occupied the oilfields near Basra in late 1914. A decision was then made to push up-river towards Baghdad, but this ill-fated expedition was supported by thinly stretched supply lines using river steamers and was cut off, surrounded and ultimately defeated at Kut-al-Amara. A huge effort was made to support a renewed campaign, with heavy reinforcements from India, by improving the port of Basra, building roads and railways and introducing more and better river steamers. Baghdad fell on 11 March 1917.
The battles of the Italian Front were fought mainly by Italian and Austro-Hungarian forces from 1915, with substantial Franco-British and German reinforcements from late 1917. The front traversed mountainous terrain, posing huge logistical problems for both sides in supplying their troops. The supply lines even included extensive use of aerial ropeways to reach troops at high altitudes, especially during the freezing winters.
Fighting afflicted Africa throughout most of the war. A long-drawn-out campaign was fought against German colonial forces in east Africa, who increasingly lived off the land and used guerrilla tactics against British forces that were mainly recruited locally and in India. While road, rail and river transport were used where feasible, due to the harsh and remote terrain supply lines relied heavily on African porters. It is estimated that over 1 million Africans were recruited or conscripted as carriers by the belligerents and they, together with the civilian population, suffered most of the casualties.
The adequacy of transport and supply networks played a major role in shaping strategies for operations throughout the First World War and in influencing their success or failure. Huge investments were made to improve the logistical support for operations, and by 1918 these had reached levels of sophistication that were ultimately capable of supporting the offensives that brought the war to a close.
With the end of hostilities the networks and equipment took on new roles, initially in supporting reconstruction of the devastated areas. Some light railways continued in operation for years after the guns fell silent, while much of the equipment was sold off and continued in operation, sometimes for decades, in many parts of the world. For Britain's railways the world was never the same. Motor transport had matured and thousands of War Department lorries were purchased by ex-servicemen and offered increasingly effective competition. The next war was to show the true military potential of motor transport, while the day of the horse was to pass for ever.