4.) A force of Germans, three times as strong, overpowered two Russian corps. During that attack Samsonov and a part of his staff were killed. That, and the disruption of liaison, was the reason reinforcements were not sent up from the other corps and the Germans succeeded in invading the Russian rear (see map No. 1). 5.) The remainder of Samsonov's army, about 80,000 men, became surrounded by 240,000 Germans, and, left without leadership, in the midst of an extremely critical and dangerous operation, on unfamiliar territory, it was shattered. _Only under such an unfortunate combination of circumstances could a threefold strong German force win the battle in a tactical sense. But, from the strategic point of view, the Germans lost in this stage of their campaign, as this battle diverted a number of German corps from France and served a purpose of the greatest importance._ [Illustration: The Russian troops are indicated on this map by white squares; the Germans--by black. It can be seen from this map that the army of Gen. Samsonov took up positions from Usdau to Biskofsburg. The Germans attacked his flanks, i. e., Usdau, his left flank, and Biskofsburg, his right. The 1st and 6th Russian Corps were located there, as indicated by the map. It may be observed from the map that the 1st Corps was attacked by two German corps, one division and the Vistula garrisons, i. e., about 120,000 Germans attacked 40,000 Russians. The 6th Corps at Biskofsburg was put in a similar situation. Under pressure from a threefold stronger German force, the 1st and 6th Corps retreated. Thereupon the Germans fell under Neiderborg and Passenheim upon the rear of Samsonov's remaining troops, the 13th and 15th Corps. These corps were consequently surrounded by this threefold stronger force and were defeated after a heroic fight of three days.] 6.) It must be added that the entire population of East Prussia was armed, and scouting was very difficult. The Russians knew nothing about the enemy, while the latter was fully informed by the inhabitants concerning the Russians and knew every step these were making. That is why the German attack came as a surprise. 7.) The assertion that Rennenkampf had 400,000 men and intentionally did not come to Samsonov's aid is a downright misstatement. This can be seen from the fact that the battle, which was begun on August 27, was lost in 18 hours, on the morning of August 28, and Rennenkampf, who with small forces was within three days' marching distance from Samsonov--40 miles--could not have arrived in time, particularly when we consider that he had to overcome on his way fortifications and barbed-wire defenses manned by landsturm and by cavalry.