Russian prisoners of war after the Battle of Tannenberg.

Eastern Front, 17–23 August 1914.

Movements of 23–26 August 1914. Red: Germans, blue: Russians

Movements of 27–30 August 1914.

The general staff had expected that Russia would be slow to mobilize, but the Tsar’s army defied these estimates by coming into action quite quickly against the German forces in East Prussia. There the 200,000 men of the German Eighth Army, commanded by 66-year-old Generaloberst Maximilian Wilhelm Gustav Moritz von Prittwitz und Gaffron, had been deployed to secure the eastern frontier while Germany’s main onslaught fell upon France in the west. Although the Russian army’s preparedness to conduct offensive operations was considerably less than that of the Germans, it nevertheless responded with alacrity to a French request to launch an offensive on the Eastern Front. Having moved two armies into East Prussia in mid-August, III Corps of Russian General Rennenkampf’s First Army struck the German I Corps at Stallüponen on 17 August.

Altogether the Russians fielded some 250 battalions against a German strength of about 144, although the German Eighth Army’s artillery was significantly stronger in terms of the ratio of supporting guns to battalions and of the amount of heavy artillery it had available. In addition, Russian command and control and support arrangements were generally archaic: for example, compasses were available, but few maps were issued, even at formation headquarters. Many Russian junior officers could not read maps in any case. Insufficient availability of telephone cable meant that many operational messages were necessarily sent by radio, but these were often transmitted ‘in clear’ (unencrypted) because the Russian signallers either had no codes or else the message recipients were incapable of decoding them. Meanwhile, little mechanical transport was available to the Russian army, and despite the updating action taken after Russia’s defeat by Japan in 1904 much of the army’s other supporting services and logistical arrangements were still primitive. In East Prussia in 1914 neither the Russian commander-in-chief, General Jilinsky, nor his two army commanders, General Rennenkampf (First Army) and General Samsonov (Second Army) displayed more than average competence as commanders, while at the same time the dislike of Rennenkampf and Samsonov for each other was well known. On the other hand, events on the German side would reveal shortly that the professional ability and judgement of the Eighth Army commander, Generaloberst von Prittwitz und Gaffron, also failed to measure up to that which was expected of an army commander.

In response to the Russian attack, von Prittwitz und Gaffron ordered I Corps, commanded by General der Infanterie Hermann von François, to withdraw his corps to Gumbinnen. But von François refused to do this and instead attacked the Russians, taking some 3,000 prisoners before at last being forced to fall back to Gumbinnen, albeit with the loss of seven guns. Meanwhile, General der Kavallerie (later Generalfeldmarschall) Anton Ludwig August von Mackensen’s XVII Corps43 and Generalleutnant (later General der Infanterie) Otto von Below’s I Reserve Corps moved to reinforce von François, arriving at Gumbinnen at about midday on 20 August. Gumbinnen was then the scene of the next clash, where von François attacked the Russian flank that morning and took a further 5,000 prisoners. Von Mackensen’s XVII Corps was, however, less fortunate. It arrived at Gumbinnen ahead of von Below’s corps and was immediately committed to the battle, where a local Russian advantage in artillery first halted the German advance and then broke the newly arrived corps. There followed the rare sight of an entire German corps rendered non-effective, one division actually breaking and fleeing the battlefield, with many of its soldiers retreating as far as fifteen miles before their flight was finally halted. Although they had lost about 19,000 men, Gumbinnen was a victory for Rennenkampf’s First Army, but it had been achieved in relative isolation, as General Jilinsky lacked both the aptitude and the essential command and control facilities to coordinate the actions of his two armies successfully and thus exploit the Russian success.

In the belief that his rival’s success at Gumbinnen heralded an imminent German collapse, and determined to gain his own victory, General Samsonov advanced his Second Army to the south of the Masurian lakes. Although these sizeable lakes now effectively divided the two Russian armies from each other such that the Second Army could no longer be supported by the First, von Prittwitz und Gaffron assessed that the Russian advance was so strong that the whole of the Eighth Army should now withdraw west of the River Vistula. At 19.00 hours on 20 August he issued the necessary warning order and notified by telephone chief of the general staff Generaloberst Helmuth von Moltke at army supreme headquarters in Koblenz of his intentions. In practice, this decision was somewhat premature, for within 24 hours two of the principal staff officers in Eighth Army headquarters had persuaded von Prittwitz und Gaffron that offensive action rather than a withdrawal was both necessary and feasible. Accordingly the army commander rescinded his earlier order for a retreat to the Vistula, thus stabilizing the operational situation and establishing the foundation from which a major German success would shortly be launched.

But for Generaloberst von Prittwitz und Gaffron it was all too late. His initial call to Koblenz had provoked horror within a high command and general staff that could not countenance either the abandonment of German territory or an apparently blatant disregard of von Moltke’s direction for the Eighth Army to counter the Russian advance by offensive rather than defensive action. Since that fateful telephone call, von Moltke had solicited reports from a number of general staff officers in key posts within the various units, formations and headquarters of the Eighth Army, and from these he had ascertained that the situation was by no means as precarious as that portrayed by von Prittwitz und Gaffron. As a result, and irrespective of the Eighth Army commander’s subsequent change of orders on 21 August, von Moltke decided to replace him forthwith.44 This decision, and von Moltke’s choice of a new commander for the Eighth Army, would have important and far-reaching consequences both for the army and, in due course, for Germany.

The officer now selected by von Moltke to take over command of the Eighth Army was 66-year-old General der Infanterie (later Generalfeldmarschall) Paul Ludwig Hans Anton von Beneckendorff und Hindenburg, whose chief of staff at the Eighth Army would be Generalmajor Erich Friedrich Wilhelm Ludendorff, an officer who had already gained a formidable reputation on the Western Front during the siege of Liège, where he had served as deputy chief of staff of the Second Army. Paul von Hindenburg was born on 2 October 1847 and, having gained a commission in the 3rd (Prussian) Regiment of Foot Guards (3. Garde-Regiment zu Fuß), served as a junior officer during the wars against Denmark, Austria and France in the period to 1871. Consistently regarded as a very capable general staff officer, as well as a pragmatic and strong leader, he rose to command an army corps as a Generalleutnant, eventually retiring from active service in 1911. He had achieved command of an army corps despite his well-known preference for service with troops rather than in staff appointments, a preference that rarely resulted in rapid advancement in the peacetime army but which earned him the loyalty and respect of those he commanded. During the later years of his service, von Hindenburg had been considered as a possible contender both for the post of chief of the general staff and for that of Prussian minister of war, but this did not happen. When he retired as a corps commander in 1911 his last first-hand experience of a major conflict had been as an infantry junior officer in 1871, so that when von Hindenburg was recalled to serve his country as commander of the Eighth Army in late August 1914, almost half a century had passed since he had been at war. Nevertheless, the formidable combination of army officer training, the general staff system and a rigorous process of selection for high command – together with the inherent ability and personal qualities von Hindenburg brought to his new assignment – ensured that the right man had been found to produce a German victory in East Prussia. In addition, this was an area that von Hindenburg already knew well, not only due to the number of manoeuvres and general staff training exercises staged there but also because he had been born in Posen (modern Pozna in Poland) in East Prussia.

Dressed in his old 1911-era uniform, von Hindenburg was met by his new chief of staff at the main railway station in Hannover on 23 August, from where they would travel on together to Eighth Army headquarters. Generalmajor (later General der Infanterie) Erich Friedrich Wilhelm Ludendorff45 was a very different man from von Hindenburg, but the personalities of the two generals complemented each other very well. Born in 1865 and in due course commissioned into the infantry, Ludendorff had no direct experience of combat or of a major conflict prior to 1914. Unlike von Hindenburg, however, he readily accepted that a career in the general staff was the route to speedy professional advancement, and having achieved membership of the staff he quickly demonstrated his aptitude, intellect and professional abilities. Despite his undoubted professional competence, he also acquired a reputation as an ambitious, mercurial, violent and abrasive officer who carried these less-positive traits into his approach to the organization and conduct of warfare. His vision of modern conflict was one of ‘total war’, waged to the uttermost extent of the resources of the nation, with little thought for matters of morality or principle if these should prejudice the army’s operations. From 1904 to 1913 Ludendorff had worked in the operations and mobilization department of the general staff, rising within it to head that department from 1908 until 1913. In that capacity he had been very directly involved in the several measures proposed to increase the size of the army in the pre-war years and had suffered the frustration of seeing the increases essential to the success of the Schlieffen Plan refused by the government in 1912 and 1913. Indeed, he had also been an important contributor to von Moltke’s operational review and modification of various aspects of the Schlieffen plan, having worked closely with him in the years prior to the outbreak of war. So it was, at Hannover Hauptbahnhof (the city’s main railway station) on 23 August 1914, that the leadership duo that would just a year later assume total command of the German army for the remainder of the war, was formed. The two officers’ onward journey to the Eighth Army headquarters at Marienburg (now Malbork) on the Vistula took them north and east from Hannover, and they arrived there later that day. En route they developed their own strategy to deal with the Russians, and on 25 August von Hindenburg signed off the operation order that committed the Eighth Army to what would become known as the Battle of Tannenberg, a defining moment not only of the fighting on the Eastern Front but also of the wider war. On 26 August von Hindenburg was promoted Generaloberst.

In fact, the operations staff at the headquarters of the Eighth Army had already produced a design for battle which virtually mirrored that devised by von Hindenburg and Ludendorff on 23/4 August. There, the chief of operations, Generalmajor Grünert, but more particularly his deputy, Oberstleutnant Max Hoffman, had also identified the disjointed command and control arrangements between the two Russian armies and the very different operational approaches of Rennenkampf and Samsonov. They assessed that this offered the Eighth Army an excellent opportunity to isolate and destroy the two Russian armies separately by conducting a holding action against one Russian army while concentrating and employing the maximum force against the other. In addition, the physical barrier provided by the Masurian lakes further exacerbated what was already the virtually non-existent coordination between the two Russian armies.

Given Samsonov’s over-optimism and recklessness – even now he was pushing his Second Army onwards at best speed in order to attack the German right, with his exhausted infantry regiments marching up to twenty kilometres a day – and Rennenkampf’s caution, the Germans judged that Samsonov clearly posed the greater threat. A captured Russian map showing the First Army’s operational plan, together with the steady flow of intelligence gleaned from German intercepts of Russian radio traffic (all still sent in clear), tended to confirm this assessment. However, if the Germans had miscalculated and Rennenkampf should break through on the northern flank, which was held by a predominantly cavalry force of just one division necessarily deployed on a frontage that exceeded thirty kilometres, then the Eighth Army risked an overwhelming attack into its rear area while its main combat units were still dealing with Samsonov to the south. In any event, the meeting of minds between the new commander and his chief of staff and the in-place operations staff of the Eighth Army meant that the army’s new offensive could be launched in fairly short order.46

As ever, the railway played a crucial part in moving major elements of the German corps speedily and largely undetected to concentrate against the Russian Second Army to the south. The German I Corps was still de-training to the west of Tannenberg on 25 August following its move south-west from Gumbinnen when Ludendorff, concerned by the threat posed by Rennenkampf, ordered its commander, General der Infanterie Hermann von François, to attack Samsonov’s Second Army forthwith. This was despite the fact that none of the I Corps’ heavy artillery was by then available and that neither I Reserve Corps nor XVII Corps would be able to support such an attack as both corps were still moving south by road to join the battle against Samsonov. At first von François refused to launch such an ill-judged venture, but he was then visited by von Hindenburg, Ludendorff and Hoffman. The outcome of the ensuing discussion was a statement by von François that, if the attack order were indeed to be confirmed, he would only agree to carry it out on the understanding that the resulting action would unavoidably have to be carried out by the infantry alone! Hoffman, who was undoubtedly more in tune with the Russian deployment and activities than Ludendorff, supported von François’ decision but did not declare this to the new chief of staff. Fortuitously, however, just then intelligence was received that Rennenkampf’s progress was sufficiently slow for his army to be unable to threaten the Eighth Army’s rear. At the same time, Samsonov had ordered a pursuit of what he had mistakenly assessed to be a still-demoralized and routed German XX Corps commanded by General der Artillerie Friedrich von Scholtz.

As a result, the original assessment of the Russian intentions made by Hoffman and Grünert was validated. Von François was no longer required to carry out his premature attack, while Samsonov’s Second Army was drawn even more deeply into the German trap. Battle was finally joined when Samsonov launched his own attack at dawn on 27 August, advancing north-westwards on a general line from Allenstein to Osterode. At that stage the two corps commanded by von Below (I Reserve Corps) and by von Mackensen (XVII Corps), which had deployed to the north and south of Tannenberg, fell upon the Russian right. By that evening the Russian advance had been halted, with many casualties sustained. Samsonov, however, was relatively undisturbed by this turn of events and still anticipated the imminent arrival of the First Army from the north. In the meantime, early that morning von François’ I Corps – now with its full complement of heavy artillery available – had begun a seven-hour bombardment of the Russian left, accompanied by a series of attacks that virtually annihilated the Russian corps on the Second Army’s left wing. Samsonov threw five more divisions into the battle, but they failed to break through the German forces that had by then almost encircled him. By nightfall on the 27th the Russian army group commander, Jilinsky, was at last becoming aware of the disastrous situation concerning his Second Army and ordered Rennenkamp to hasten his attack from the north.

On 28 August the fighting continued, and the German encirclement of the Second Army was completed when von François again disobeyed an order from Ludendorff, which on this occasion required him to move to assist von Scholtz’s XX Corps. Fortunately, XX Corps did not need this assistance, and by driving instead upon Neidenburg (now Nidzica), von François’ I Corps effectively cut off the Russians’ potential escape route to the south. Although the remnants of the ensnared Second Army fought on bravely and enjoyed some local successes, including the temporary recapture of Neidenburg, the end was not in doubt. Late on the night of 29 August Samsonov walked alone into the dense fir woods, took out his pistol and shot himself. The last units of his decimated army dug in and continued fighting until the morning of 31 August, when they surrendered. By then the last of the Second Army’s ammunition was gone, and there was no hope of resupply or relief. In the defeat of the Second Army 50,000 Russians had been killed or wounded, with 92,000 prisoners taken by 31 August – the ‘day of harvesting’ as von Hindenburg termed it – together with some 500 guns.

Of the great haul of prisoners taken, no fewer than 60,000 were directly attributable to the actions of von François, who had yet again modified Ludendorff’s orders for his I Corps at the end of the main battle, thus ensuring that the remaining Russian troops could not infiltrate away to the south and east. Although his intuitive command of I Corps had been most effective in accordance with the concept of Auftragstaktik, and he was a key contributor to the German victory against the Second Army, von François had not endeared himself to Ludendorff during the Battle of Tannenberg. Consequently, despite his clear professional ability and suitability for advancement and high command, von François was destined to remain a corps commander throughout the war.

Meanwhile, now fully aware of Samsonov’s fate, Rennenkampf withdrew his First Army, only to find himself being pursued by German forces now reinforced by an additional two corps from the Western Front. During the ensuing Battle of the Masurian lakes, fought between 5 and 15 September, von Hindenburg’s forces finally crippled Rennenkampf’s army, which lost more than 125,000 men including 30,000 as prisoners, together with 200 guns. However, the defeat of the Russian First Army was not as decisive as that of the Second Army: Rennenkampf managed to disengage and withdraw part of his command successfully, often marching his men more than thirty kilometres a day on congested roads in blistering heat. The end of this follow-on battle by the Masurian lakes marked the conclusion of the Battle of Tannenberg, a German victory that had great significance for the wider conflict, shaping its future course and that of European history, but particularly that of tsarist Russia.

Tannenberg also assured the future prominence and fortunes of von Hindenburg and Ludendorff. The former continued as commander-in-chief on the Eastern Front throughout 1915, achieving several further successes. By the end of that year von Hindenburg had become a household name within Germany and internationally, and when the Kaiser relieved General der Infanterie Erich Georg Sebastian von Falkenhayn of his post as chief of the general staff in August 1916 von Hindenburg assumed that appointment, becoming in practice Germany’s supreme warlord throughout the remaining years of the war.

Meanwhile, Ludendorff continued as von Hindenburg’s principal adviser, and so from August 1916 he exerted a very significant influence upon many aspects of an army that was by then engaged in a modern, industrialized war of attrition. He addressed the army’s doctrine, tactics, technology and organization with great energy, as well as the key policies and practicalities that affected the means of industrial production necessary to support such an army. Whereas von Hindenburg was unquestionably Germany’s military and national figurehead during those years, he lacked the sheer ability of his subordinate. Ludendorff’s was the intellect and the brain that drove the nature and spirit of the army and, arguably, that of the German nation in arms from 1916 to 1918, while von Hindenburg’s great skill was to recognize Ludendorff’s considerable, if sometimes erratic, attributes and his own limitations, simultaneously directing, supporting and focusing the former while not deluding himself over the latter. The enormous breadth of power and responsibility that was accorded to von Hindenburg and Ludendorff from 1916 made them true warlords of their time and exemplars of more than a century of Prussian and German military professionalism. For both of these senior officers their ultimate wartime achievements were the culmination of a process that began in East Prussia during August–September 1914 at Tannenberg and the Masurian lakes.