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In the south, however, things were going much worse. Throughout the 8th of September the German forces in the north hammered at the Russian forces facing them, forcing an orderly retreat eastward. Hindenburg's southern divisions began their attack on the 7th of September, with the battle proper opening the next day. He sent his most capable units, the I Corps and XVII Corps, far to the south of the lines near the middle of the Lakes, and sent the 3rd Reserve Division even further south to Lyck, about 30 miles from the southern end of Rennenkampf's line. But unlike Rennenkampf, Hindenburg had enough forces not only to cover the entire front in the Insterburg Gap, but had additional forces "left over". Then, like Rennenkampf, Hindenburg fed his newest troops into the northern end of the line and planned an offensive against the south. For the first time since the opening of the war, the Germans now had numerical superiority. Adding to his force were two newly arrived Corps from the Western Front, the Guards Reserve Corps and the XI Corps. He was able to safely ignore the Russian right (in the north), which was in front of the extensive defensive works outside of Königsberg. German efforts at mopping up the remains of the Second Army were essentially complete by 2 September and Paul von Hindenburg immediately started moving his units to meet the southern end of Rennenkampf's line. General staff of the German 8th Army during the battle. All in all, he appeared to be in an excellent position to await the arrival of the Russian Tenth Army, forming up to his south. His forces also included two infantry divisions held in reserve. Bolstering his forces were the newly formed XXVI Corp, which he placed in front of Königsberg, moving his more experienced troops south into the main lines.
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Realizing his forces were too spread out to be effective, he ordered a withdrawal to a line running from Königsberg's defensive works in the north, to the Masurian Lakes near Angerburg in the south, anchored on the Omer River. On 31 August, with Tannenberg lost, Rennenkampf had been ordered to stand his ground in the event of a German attack. Of course the Germans were also very far away, but unlike the Russians, the Germans could easily close the distance using their extensive rail network in the area. An attack by the German Eighth Army from the west would flank the entire army. In order to get even this close his units had to rush southward, and were now spread out over a long line running southward from just east of Königsberg. When the nature of the German counteroffensive became clear, Rennenkampf had his troops move as quickly as possible to help, but by then it was too late.īy the time the battle proper ended on 30 August (Samsonov committed suicide on 29 August), the closest of Rennenkampf's units, his II Corps, was still over 45 miles (70 km) from the pocket. When Samsonov became aware of the German movements he requested that the gap between the two armies be closed up, but Rennenkampf was in no hurry to act on this, leaving Samsonov isolated many miles to the southwest. The commander of the Second, Alexander Samsonov, had publicly criticized Rennenkampf some years earlier (about the Battle of Mukden in 1905), and it is said that the two had come to blows over the matter.
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The counter-offensive was made possible, in part, due to the personal enmity between the two Russian Generals - which was well known to the Germans. Hoffman's plan was quickly implemented, culminating in the complete destruction of the Second Army at the Battle of Tannenberg between 26 and 30 August 1914.
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However, Colonel Max Hoffmann developed a plan to attack the Second Army as it attempted to maneuver north over some particularly hilly terrain. Meanwhile the Russian Second Army approached from the south, hoping to cut the Germans off in the area around the city. The Russian offensive in the east had started well enough, with General Rennenkampf's 1st Army (Army of the Neman) forcing the Germans westward from the border towards Königsberg.
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