Topic: Military History
(For clarity, German units are rendered in italics.)
As the Austro-Hungarian armies marched across Galicia toward their rendezvous with disaster, Russian troops commenced the invasion of East Prussia. General Pavel Karlovitch Rennenkampf’s First Army crossed the frontier on 17 August, rather earlier than the Germans had expected. This was the northern prong of the Russian offensive, directed against Konigsberg. On 18 August its vanguard was repulsed with heavy casualties by Eighth Army’s I Corps (Lieutenant-General Hermann von François) around the town of Stallupönen, some ten miles inside the frontier. But he had attacked without orders and when the Eighth Army commander, General Maximilian von Prittwitz und Gaffron, heard what had happened he ordered François to break off the battle and retire. Prittwitz intended to consolidate his forces some ten miles farther west, around the town of Gumbinnen. Once François’ corps vanished from their front the Russians resumed their deliberate advance.
By 20 August, Prittwitz had the bulk of his army drawn up in the vicinity of Gumbinnen: I Corps on the left, XVII Corps (Lieutenant General August von Mackensen) in the center and I Reserve Corps (General Otto von Below) on the right—six infantry divisions and a cavalry division in all. Intercepted radio messages (the Russians were blithely transmitting in the clear) indicated that Rennenkampf had declared a rest day for his army on 20 August, so Prittwitz decided to attack.
On the left after a hard fight, I Corps gained the upper hand over Russian XX Corps but in the center things went awry. Mackensen committed XVII Corps to a frontal attack against the Russian center that broke down after heavy fighting. Under violent fire from the Russian artillery the German infantry panicked and fled, followed closely by their artillery. Prittwitz thereupon ordered I Corps and I Reserve Corps to retire also. That evening he telephoned Moltke at OHL to announce that Eighth Army had been defeated at Gumbinnen and would probably be compelled to retreat behind the Vistula River, abandoning East Prussia completely. Prittwitz’s alarm was compounded by the news that Russian Second Army (General Alekesander Vasilevich Samsonov), with five corps and a cavalry division, had commenced its attack out of the Polish salient, moving northwest into East Prussia. Here there was nothing to oppose the Russians except XX Corps (Lieutenant-General Friedrich von Scholtz) and some Landwehr troops. Fearing that Second Army’s advance would cut the rear communications of the German forces standing against First Army to the north, Prittwitz succumbed to panic. Late that evening he telephoned Moltke again, confirming his decision to quit East Prussia.
Though the possibility of losing East Prussia had always been recognized, Moltke shrank from its consequences. To yield the ancient heartland of the Hohenzollern monarchy in the first weeks of the war would deal an enormous psychological blow to the army and the nation. Agitated protests poured into OHL from East Prussian landowners and from the Kaiser himself. General von François, who was convinced that the situation was not as dire as Prittwitz supposed, protested directly to the monarch against the proposed withdrawal. On 21 August, therefore, Moltke decided that Prittwitz and his chief of staff, Major General Alfred von Waldersee, must be sacked. Looking around for suitable replacements his eye fell on one Major-General Erich Ludendorff, a man who had recently made his mark during the siege and capture of the Belgian fortress of Liege. But Ludendorff was too junior to be given command of Eighth Army; he would be made chief of staff. For its new commander Moltke resorted to the retired list. From it he selected Colonel-General Paul Ludwig Hans Anton von Beneckendorff und von Hindenburg, a veteran of the Franco-Prussian War with a solid reputation, who had retired in 1911. In response to Moltke’s telegram inquiring when he could report for duty, Hindenburg responded tersely, “Am ready.” Still wearing the obsolete blue uniform of a Prussian general (he had not had time to be fitted for the new field gray) Hindenburg joined Ludendorff on the train that was to carry them both east.
Meanwhile, ignorant of the fact that his fate had been settled Prittwitz had somewhat recovered his balance. Thanks to the Russians’ habit of transmitting radio messages in the clear, supplemented by aerial reconnaissance, he had good information of his opponents’ dispositions and intentions—knowing, for example, that having gotten the better of the fighting at Gumbinnen First Army was staying put. Rennenkampf judged that before the advance could resume his army’s supply situation must be cleared up. The offensive into East Prussia had been launched before the supply services had been full mobilized—this in response to insistent French pleas for early action. Moreover, owing to a difference in gauges Russian trains could not use the East Prussian rail net. It was thus proving difficult to furnish the rations, fodder, ammunition and replacements that the army needed. Farther south, Samsonov’s Second Army was experiencing similar problems as it advanced into East Prussia.
Armed with this knowledge his staff proposed, and Prittwitz agreed, to leave only a thin screen of cavalry and Landwehr troops facing First Army. The bulk of Eighth Army would move south to confront Second Army, an operation made possible by efficient staff work and the well-managed East Prussian rail net. This was the situation on 23 August when Hindenburg and Ludendorff arrived at Eighth Army headquarters—bearing the news to Prittwitz and Waldersee that they had been sacked. The stage was thus set for the storied Battle of Tannenberg.
