Alexander Samsonov advanced from the south towards the Vistula River. Momentarily panicked, Eighth Army commander Maximilian von Prittwitz notified OHL of his intent to withdraw his forces into Western Prussia. The Chief of the German General Staff, Generaloberst Helmuth von Moltke, responded by relieving Prittwitz and replacing him with Hindenburg. Tannenberg Upon arriving at Marienberg on 23 August, Hindenburg and Ludendorff were met by members of the 8th Army's staff led by Lieutenant Colonel Max Hoffmann, an expert on the Russian army. Hoffman informed them of his plans to shift part of the 8th Army south to attack the exposed left flank of the advancing Russian Second Army. Agreeing with Hoffman's strategy, Hindenburg authorized Ludendorff to transfer most of the 8th Army south while leaving only two cavalry brigades to face the Russian First Army in the north. In Hindenburg's words the line of soldiers defending Germany's border was "thin, but not weak", because the men were defending their homes. If pushed too hard by the Second Army, he believed they would cede ground only gradually as German reinforcements continued to mass on the invading Russians' flanks before ultimately encircling and annihilating them. On the eve of the ensuing battle, Hindenburg reportedly strolled close to the decaying walls of the fortress of the Knights of Prussia, recalling how the Knights of Prussia were defeated by the Slavs in 1410 at nearby Tannenberg. On the night of August 25, Hindenburg told his staff, "Gentlemen, our preparations are so well in hand that we can sleep soundly tonight". On the day of the battle, Hindenburg reportedly watched from a hilltop as his forces' weak center gradually gave ground until the sudden roar of German guns to his right heralded the surprise attack on the Russians' flanks. Ultimately, the Battle of Tannenberg resulted in the destruction of the Russian 2nd Army, with 92,000 Russians captured together with four hundred guns. while German casualties numbered only 14,000. According to British field marshal Edmund Ironside it was the "greatest defeat suffered by any of the combatants during the war". Recognizing the victory's propaganda value, Hindenburg suggested naming the battle "Tannenberg" as a way of "avenging" the defeat inflicted on the Order of the Teutonic Knights by the Polish and Lithuanian knights in 1410, even though it was fought nowhere near the field of Tannenberg. After this decisive victory, Hindenburg repositioned the Eighth Army to face