
/battle-of-grunwald-large-56a61c1f5f9b58b7d0dff668.jpg)
This move was helped by the lack of communication between the two Russian commanders, who disliked each other. Developing Hoffman's original plan, Ludendorff concentrated six divisions against Samsonov's left flank and took a calculated risk to withdraw the rest of the German troops from Gumbinnen and move them to face Samsonov's right flank, leaving only a cavalry screen against Rennenkampf. The Germans then got lucky when they intercepted an uncoded Russian message indicating that Rennenkampf was in no hurry to advance. However, on 23 August Prittwitz was replaced by General von Hindenburg whose chief of staff, Ludendorff, immediately confirmed Hoffmann's plan to strike at Samsonov's left flank. By this time Samsonov's forces had crossed the southern frontier of East Prussia to threaten the German rear, defended by only three divisions.įaced with imminent attack, Prittwitz, commander of the 8th Army, approved Lieutenant Colonel Hoffman's idea to attack Samsonov's left flank, aided by another three divisions moved by rail from the Gumbinnen front. The plan began well at Gumbinnen on 20 August, when Rennenkampf's First Army defeated eight divisions of the German 8th Army on its eastern front. Rennenkampf's First Army was to converge with the Samsonov's Second Army to give a two-to-one numerical superiority over the German 8th Army, which they would attack from the east and south respectively, some 80km (50 miles) apart. Two Russian armies invaded German East Prussia in August 1914.

This required mobility and nimbleness unfortunately the Russians had neither. Allied with France and Britain, Grand Duke Nicholas, the Russian commander, agreed to help relieve the French, under attack from Germany, with an offensive in East Prussia.
