European armies’ increasing reliance on railways culminated in one of the world’s bloodiest wars.

On the afternoon of July 30, 1914, government telegraph offices in St. Petersburg burst into staccato chatter. Almost immediately, railroad yards in Moscow, Gdansk, Smolensk, and across the far-flung Russian Empire came alive with activity. Guards were quickly dispatched to railheads and railway bridges. Locomotives along the Polish frontier were called home. Rail companies jettisoned civilian freight from boxcars and readied passenger cars for masses of soldiers, who would be marching to board them from concentration points across Russia.

In Vienna, then Berlin, then Paris, similar telegraphs clattered. Sealed orders were opened, and rail yards in Cologne, Innsbruck, Rouen, and countless other cities began implementing plans for general military mobilizations. No Frenchman had yet fired on a German. Not one Austrian had looked down his rifle at a Russian. But World War I had begun, and its first battle would be a race to the rail yards.

The velocity of warfare had changed since the great national wars of Napoleon 100 years earlier. The advent of efficient railway and telegraph systems connecting distant parts of each country accelerated the speed with which a nation could commit its troops to the battlefield. When European officers had returned home after observing the American Civil War, they brought with them a Pandora’s box of ideas that would help consume a generation of young men a half-century later.

The potential for using the railway system as a military tool was not new. The earliest large-scale troop movement by rail took place in 1839, when the British army moved its 10th Regiment of Foot over the Liverpool & Manchester Railway to suppress a threatened uprising in Manchester. The troops arrived quickly, intact, and without being exhausted by a long march. In 1850 Austria bullied Prussia into diplomatic submission by using rail cars to move 75,000 soldiers and 8,000 horses to the Silesian border in three weeks, and in 1859 France moved 130,000 soldiers to Genoa by rail during its war with Austria.

The military value of the “iron horse” was not lost on Prussia, the Continent’s rising power. In 1843 a young Helmuth von Moltke wrote, “Every new railway development is a military benefit, and for national defense it is far more profitable to spend a few million on completing our railways than on new fortresses.” In 1860 von Moltke backed up his words; as chief of the Prussian general staff, he added a Railway Section to the military council. A contemporary would write that von Moltke never made an important decision without consulting the German railway timetables.

Four years later, Prussia made sporadic use of its rail lines in its war against Denmark, moving more than 15,000 men and 4,600 horses 175 miles in six days. However, it was not until 1866, after military planners had digested reports of the U.S. conflict, that Prussia established its first military railway units. These 200-man detachments, modeled after the U.S. Construction Corps, were commanded by army engineers but staffed by Prussian state railway employees who were responsible for railway maintenance and wartime destruction.

In the summer of 1866, when war with Austria broke out, von Moltke used trains to move troops to the Bohemian border. Because Prussian rail lines generally radiated from Berlin, his plan resulted in an arc-shaped front of some 200 miles, an arrangement that became known as his “strategy of external lines.” In all, nearly 200,000 troops and 55,000 horses rode the rails to the front.

Once they arrived there, however, the system broke down. The arrangements for unloading supplies were nowhere near as well planned as they were for loading supplies, so freight car after freight car backed up from the railheads, forcing soldiers to forage for their food. Four years later, von Moltke would use the same basic approach to mobilize against France. Unlike the Austrians, however, the French had a highly efficient railway system that could quickly be adapted to defensive needs. Their practice of issuing soldiers their rations aboard trains made travel much faster than the German method, which required the trains to stop while soldiers disembarked for coffee and food. Furthermore, France had fewer large railway companies, allowing greater track-gauge standardization. Unlike the German lines, four-fifths of the French rail network was double-tracked, which allowed trains to run to and from the frontier without needing to find a siding or build return runs into already-complicated timetables.

The importance of railroad timetables hearkened back to the American Civil War experience. Then, poor coordination between military and civilian railway managers in the Confederacy had led to dreadful incidents of trains being sent in the wrong directions by local commanders. Entire rail lines were backed up while conscripted railway employees spent days or even weeks locating trains and moving them out, one by one, until all trains were heading in the right directions. The United States, less concerned about protecting private property rights, moved quickly to place major railroad companies under semi-national control, but even that system gave commanders fits, as thousands of  cars shuttled men between hundreds of often-in-compatible lines. Both North and South took far too long to realize that interconnected railroad systems handling hundreds of cars cannot simply change directions at the whim of a local commander.

Prussia took these lessons to heart. Fearing that the French armies would beat Prussian forces to the Franco-German border, von Moltke sent his advance units to the frontier by rail as rapidly as possible. Meanwhile, thirteen corps prepared to move toward the front along nine Prussian and German railway lines. A commission of military and civilian officials supervised each of the lines. By following complicated timetables and curtailing civilian traffic, Prussia moved nearly a half-million men, with horses, guns, and equipment, to their concentration areas in 11 days.

As in the Austro-Prussian War, however, mobilization outpaced supply. Sending men into France to seize the initiative, von Moltke created a gap between his soldiers and their forward rail depots that widened as his troops advanced. Supplies did not arrive at the depots on time, and what did arrive was not processed quickly. The supplies then had to be taken by wagons to the rapidly advancing troops. At the front, the end result was a significant shortage. So, as in Bohemia, Prussia’s troops foraged for provisions.

Prussian engineers did try to advance their railheads westward to facilitate logistics once the armies were in France, but fortresses at Toul, Metz, Rheims, and other strategic locations kept critical railway lines under French guns, preventing the Prussians from using those extended lines for the balance of the war. Despite the best efforts of Prussian engineers to lay tracks around French fortresses and repair lines destroyed by the retreating French army, military livestock died in idle boxcars, and ambulance trains returning to Germany were often kept waiting for intolerable periods.

The only German line running into eastern France, the Landau–Nancy line, was so backed up that trains took two days to cover the first 18 miles, and one out of seven trains sent from Germany returned without ever reaching Nancy.

On the French side, the Est (East) Railway—the major line from Paris to the Rhine—along with its sisters, the Nord (North) and the Paris–Lyon– Méditerranée lines, had performed admirably at the war’s outset. During the conflict’s first three weeks, some 300,000 men, 65,000 horses and 6,600 guns were conveyed to the front with only two train accidents—an impressive record. However, French military officials failed to have units ready to board their trains on time. Some left half empty while others contained several different amalgamated units that had disembarked at the wrong times. At the other end of the line, French commanders failed to have destination orders ready when the trains arrived, resulting in rolling stock backing up as whole regiments waited in their cars for instructions.

In retrospect, the French railways performed just as efficiently as their Prussian counterparts, and often more efficiently. But lack of adequate coordination and planning by the French government negated France’s natural advantage in rail assets, and the generally fine performance by civilian railway officials has been largely overlooked. In the end, the French military was not able to quickly assemble enough troops to follow through with its plan to launch a major invasion of Germany.

The Franco-Prussian War provided valuable lessons that Europe’s other powers tried to incorporate into their own systems. Ambulance trains, previously used only sporadically and with little success in Europe, were now incorporated into the military rail systems of the major European armies. Furthermore, during the small wars that field artillery, and heavy artillery.

Detailed traffic and deployment plans were made with input from the Railway Section of the general staff, down to the time allowed for disembarking a train-load of infantry (15 minutes), horses (20 minutes), or artillery (two hours) and for meal stops (45 minutes to one hour). To deal with the realities of mobilization, German staff officers were put through “railway maneuvers,” or war games in which rail lines were declared destroyed or deployment plans were abruptly changed, forcing officers to improvise.

After the Franco-Prussian War, the Germans had modified their railways to accommodate military requirements. The Prussian gauge became the standard track width throughout Germany. French tunnels and bridges, however, tended to have lower clearances than German bridges. To prevent German locomotives from losing their smokestacks in France, the Railway Section required engines to adopt two-piece chimneys, giving rise to the cynical but accurate observation during the interwar years that Germans designed their military trains to fit the clearances of their neighbors’ railways.

On the other side of the Rhine, the French general staff’s Fourth (Transport) Section, through its Service des Chemins de Fer, worked closely with Est Railway officials to ensure that enough double-tracking, loops, and signal stations were in place in case of war with Germany. Plan XVII, approved in 1913, called for 56 pairs of trains to run every 24 hours along the main double-track lines. The most immediate military needs would be met by moving units with their supplies during the first 11 days. Then a 12-hour break would allow the rail systems to make up for any delays or mishaps, followed by a five-day general mobilization.

Austria-Hungary also had railway deployment plans, but because it faced different possible combinations of enemies, its plans were much more complex than those of Germany or France. The Austrian chief of staff’s “War Case B” envisioned a war only against Serbia, but by 1912 consideration was given to “War Case R,” which foresaw such a war bringing Russia’s weight against Austria. Among the Great Powers, only Britain—comfortably isolated from the Continent—and vast, mismanaged Russia lacked thorough, updated rail deployment plans.

The wild card, in German thinking, was Russia, with a standing army of more than 1.4 million men, compared to Germany’s 856,000. Because the average Russian soldier had to travel 600 to 700 miles to the front, the country’s 7.5-million-man reserves could be defeated in detail if Germany could mobilize its 4 million reserves, defeat France, and get to the Eastern Front in time to defeat Russia’s slowly advancing forces. Furthermore, since Russia’s eight major rail lines radiating from the Moscow–St. Petersburg axis were woefully inadequate to move armies in a north-south direction, Germany would have an advantage shifting forces between theaters on the Eastern Front.

In making his calculations in the early 20th century, Schlieffen had realistically assumed that Russia could move no more than 200 military trains per day. After 1910, however, Nicholas II allocated funds to improve railways serving the Polish frontier, and the French government provided additional railway loans; by 1914, 360 Russian trains could reach the front daily. As a result, Russia’s mobilization plans put the army on a schedule such that it would take its forces only three days longer than Germany’s to reach the front. The German high command was aware of some of the Russian improvements, and from its standpoint, 1914 was probably the last year that the Schlieffen Plan would have any chance of success.

An oft-repeated story is that the requirements of mobilization, the child of the European railway systems, dictated the rapid progression from crisis to war in the last six days of July 1914. There is some truth to it. When Kaiser Wilhelm II realized that his assurances of support to Austria-Hungary could lead to a war involving most of Europe, he took tentative steps to limit the conflict to the Eastern Front. Summoning Chief  of Staff Helmuth von Moltke (nephew of the Franco-Prussian War’s von Moltke) on August 1, Wilhelm informed him of a tentative proposal to guarantee British and French neutrality in a Russo-German war. “Now we can go to war against Russia only,” he declared to the astonished general. “We simply march the whole of our army to the East.”

Von Moltke, seeing years of careful preparation thrown into chaos by this last-minute change, flatly objected. “Your majesty,” he pleaded, “it cannot by done. The deployment of millions cannot be improvised. If your majesty insists on leading the whole army to the East it will not be an army ready for battle but a disorganized mob.” The kaiser chided von Moltke, “Your uncle would have given me a different answer.”

That day, Germany declared war on Russia. On August 2, upon word that the proposal for Franco-British neutrality had been a misunderstanding, von Moltke was given the green light to send German forces to the west against France and to the east against Russia. The following day, Germany declared war on France.

The refusal of France to remain neutral in the event of a Russo-German war, not Germany’s railway schedules, made the Schlieffen Plan an attractive option for Germany and prompted the preemptive strike envisioned by German planners since the 1890s. As to the irreversibility of mobilization, von Moltke had overstated the case. Freezing mobilization to buy time for a diplomatic solution was by no means impossible. The head of the German high command’s Railway Section, General Hermann von Staab, argued vehemently after the war that, if given the command on August 1, his railways could have transferred four of Germany’s seven armies to the Eastern frontier by August 15, leaving three to guard against a French incursion into German territory.

When war came, Germany’s mobilization moved ahead with Prussian precision. The kaiser approved mobilization on August 1, and August 2 became mobilization day 1. Civilian rail traffic exploded as Germans, French, and Italians frantically bought tickets to make their way home. Freight cars were unloaded and laden with military stores; in many cases, boxcars had their sides removed to make room for artillery pieces. Soldiers erected loading platforms, and in the first hostile act on the Western Front, an armored train bearing cars full of German infantry crossed into neutral Luxembourg to take control of the tiny principality’s railway network. On August 4, mobilization day 3, the generals put the railroads on war timetables and discontinued civilian passenger trains, except for those carrying reservists called up by their units.

Six German infantry brigades embarked to capture Liège, Belgium (the violation of Belgian neutrality prompted Great Britain to declare war on Germany), and by mobilization day 5 (August 6), masses of troops were being sent into German-occupied Alsace-Lorraine to blunt French offensives expected in that sector.

By August 18, 11,000 German trains had completed more than 3 million military passenger journeys, carried 860,000 horses, and moved thou-sands of tons of military supplies, all with remarkably few mishaps. Germany beset Europe, Asia, and Africa prior to 1914, and in strategic planning for the next great war, the major powers went to great lengths to take advantage of the iron horse in order to increase their armies’ speed and efficiency.

During the Russo-Turkish War of 1877, for instance, Tsar Alexander II had 189 miles of track built through Romania to connect Russia’s Southwestern Railway with Galatz, on the Turko-Romanian frontier. Alexander’s minister of war wrote around that time: “Railways are now the strongest and most decisive element of war. Therefore, regardless even of financial difficulties, it is exceedingly desirable to make our railway network equal that of our enemies.” The inefficiency of Southwestern Railway officials and a shortage of spare locomotives and rolling stock, however, hampered Russian efforts.

Great Britain, a pioneer in military railway use, established the Engineer and Railway Staff Corps in 1865. Commanded by railroad executives and civil engineers who had been commissioned as military officers, the corps prepared wartime plans for the quick, coordinated movement of troops to concentration areas along the nation’s many railroads. Near the century’s end, General Horatio Kitchener incorporated railroads into his campaign strategy to avenge the 1885 death of General Charles “Chinese” Gordon at Khartoum. Between 1896 and ’98, British engineers constructed a 216-mile railway that followed Kitchener’s southward advance through the Sudan. His victory at the September 2, 1898, Battle of Omdurman, securing Britain’s hold over the region, was won by troops moved and supplied by rail.

Railroads had by then become an indispensable component of British military planning. Lines began stretching in all directions from East India to the Suez, often driven by “enlightened” commercial considerations more than military ones, as efficiency of transport was of paramount concern to both mercantile and military leaders.

During the 1899-1902 Boer War, the British army introduced an innovation that presaged the development of the tank: the armored train, which was typically equipped with quick-firing naval guns, one-pounder pom-pom guns, Maxim machine guns, and firing ports for riflemen. By 1902 Britain had fielded a total of 20 such trains in South Africa. The British also mounted heavy long-range naval guns on modified rail cars, although both armored trains and rail guns were too vulnerable and too limited by their tracks to be of much use against the Boers until later in the war.

In France Paul Décauville, an agricultural machinery manufacturer, developed light, portable field rails that would prove enormously useful in the next two major wars. Set on a two-foot-gauge track, prefabricated “Décauville” railways were well suited for military purposes. The engines and rolling stock were kept in storage until needed, then transported by rail car, animal power, or their own steam to the theater of operations, where they would run on tracks laid as needed by military engineers.

Railroads played an important role in the twentieth century’s first major conflict, the Russo-Japanese War. By February 1904, when Japan launched its surprise attack on Port Arthur, Russia’s Trans-Siberian Railway, though a source of alarm to Tokyo, was as yet incapable of adequately supplying Tsar Nicholas II’s forces south of Vladivostok, because the line was broken for a stretch around Lake Baikal.

During that conflict, Japan made ex- tensive use of the captured Chinese Eastern Railway to move troops from Port Arthur through Manchuria. They routed the Russians at the Battle of Mukden by, among other things, send- ing General Maresuke Nagi’s Third Army to threaten the tsarist army’s rail lines. The badly managed Trans-Siberian Railway eventually moved nearly a million men across the Eurasian landmass about the time that Japan agreed to a negotiated peace.

During the decades preceding World War I, Germany, facing hostile powers to its west and east—France and Russia—thoroughly understood that transporting troops by rail would be the key to victory in a future war. The Schlieffen Plan, developed between 1891 and 1905, envisioned a rapid mobilization to the west. This would be followed by a wheeling attack on foot through Belgium and France, striking Paris from the north and west. Resupply of the quickly moving army would presumably be along captured French railways, the railheads lagging no more than 75 miles behind their client armies.

After France’s defeat, trains would transport Germany’s army to East Prussia, where its attack would fall just as the lumbering Russian army was invading the German homeland. It was a dangerous gamble, and it would depend heavily on Germany’s rail systems being up to the task (an estimated 650 military trains would have to run to France each day through Cologne alone). The Aachen–Landen line would have to move 2,700 tons of oats and 3,200 tons of hay each day—feed for 445,000 animals accompanying the advance.

To implement the Schlieffen Plan, Germany’s general staff dedicated specific rail lines to each of the operation’s major components. General Maximilian von Prittwitz’s Eighth Army, for instance, was assigned three double-track lines heading to the Eastern Front, while four such lines were allocated to connect the Western Front with the East. Along the French frontier, four designated lines made it possible for the German high command to transfer four entire corps from Cologne to Strasbourg in only three hours. The Schlieffen Plan was modified every year, to account for changing rail facilities and to fine-tune military priorities.

The operation called for a three-phase deployment. First, western defense troops would man the frontiers in response to a premobilization threat of war. Second, covering troops would be rapidly transported to deployment zones to protect those areas as general mobilization proceeded. This phase would last through the fourth day of mobilization. Finally, on the fifth day the main body of troops would begin moving to its designated deployment zones to begin strategic operations. The final phase would require each rail line to run 50 trains every 24 hours, with a four-hour pause built in to deal with unforeseen problems. The order of deployment was as follows: essential administrative staff first, then pioneer units and field bakeries, followed by cavalry, infantry, had been somewhat hampered by the loss of key railroad workers called up as reservists, but the only significant snags occurred when the commander of Germany’s Third Army, General Max Klemens von Hausen, demanded that two of his corps be deployed farther west than originally planned, an order that would have seriously upset the established schedules. Railway officials knew better than to upset the general staff’s intricately laid timetables, and they refused to comply. Mobilization proceeded to a successful conclusion, and hundreds of thousands of men were duly sent into the cauldron of war.

In France mobilization went almost as smoothly under Plan XVII. Over 20 days of mobilization trains moved 42 French corps (each corps required 85-car trains)–more than a million men, 400,000 horses, and accompanying supplies–to the frontiers. At Troyes, where the Est intersected north-south lines, more than 400 trains would pass on peak days, averaging one train every four minutes.

The French, unlike the Germans, exempted critical railroad workers from reserve service, but many of them, caught up by the wave of patriotism that swept France that summer, flocked to the tricolor as volunteers. As in Germany, a few incidents marred the otherwise stellar performance of the Est Railway and its associated lines. Most were rear-end collisions. Some accidents caused delays, but railway officials did a commendable job rerouting trains to their final destinations.

Farther north, Belgium quickly spirited as many trains to France as possible once it was invaded. Some 1,250 locomotives, which German planners assumed would fall into its army’s hands, made their way to safety via rail lines into northern France. These engines were later distributed among the Allies. (Several were sent by sea to assist the Russian war effort, only to be captured  by the German army—during World War II.)

The British Expeditionary Force (BEF), for its part, planned to move from the English Channel to the front by rail. Mobilization and rail transport were naturally the most chaotic where the British troops were landing—in Boulogne, Le Havre, and Cherbourg— because the French government could not control their arrivals and deployments. Ships unloading at the ports carried wildly varying numbers of men and types of equipment, and French efforts to standardize train capacities for trans- porting the British proved pointless. Trains began taking on soldiers as they disembarked from transports, and by September some 115,000 men and 46,000 horses of the BEF had ridden on 361 trains to the Belgian frontier.

On the Eastern Front, Russian mobilization exceeded all expectations, partly because Schlieffen had downplayed improvements to Russian railways. By the end of mobilization, Tsar Nicholas was able to send some 1.3 million fighting men to the Austro-German front, although disaster awaited many of them in the forests of  Tannenberg.

Austrian mobilization against Russia, however, was somewhat confused. Its initial mobilization was only directed at Serbia, in the belief that German pressure would keep Russia out of the “local” conflict. When Russia mobilized, Austria followed suit, but its chief of staff, General Count Conrad von Hötzendorf, unclear as to Russia’s intentions, sent two of his three army groups south to the Balkans against Serbia, rather than north to Galicia as a bulwark against the coming Russian onslaught.

By the end of August 1914, the railroads of the European powers had come to play a vital role in the conduct of mechanized war. Back in the 1850s, British rail car manufacturer and inventor William Bridges Adams had concluded that “Wars cannot be carried on without railways, and the railway is emphatically the offspring and tool of civilization.” The conduct of European warfare between 1866 and 1914—and particularly the onset of World War I, strongly driven by the dictates of railway timetables—vividly illustrated how civilization’s iron horse had changed military strategy, making it possible for large armies to quickly engage the enemy—and consume the blood and treasure of a continent at a rate never before seen.

JONATHAN W. JORDAN writes from Marietta, Georgia.

This article originally appeared in the Summer 2005 issue (Vol. 17, No. 4) of MHQ—The Quarterly Journal of Military History with the headline: Reign of Railroads

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