End of the battle of Vilna

At the beginning of October 1915, east of Vilna, the last great German offensive of the year on the Eastern Front died away. The German official list of battles closes the battle of Vilna on 2 October. The same day, or 19 September by the Julian calendar, is also given as its end by Russian historians, who write that the breakthrough at Švenčionys had been eliminated and the front had stabilised. The Germans, who on 9 September had struck at the junction of two Russian armies and taken Vilna, failed to encircle the Russian Tenth Army. The front came to a halt on a line from Lakes Drysviaty and Naroch through Smorgon and further south. The date is a convention, however, because the fighting in this sector did not stop from one day to the next.

Withdrawal to winter positions

At the end of September the German command on the Eastern Front decided that a further advance made no sense. General Erich Ludendorff recalled that during the slow march from Vilna towards Smorgon he realised that the operation had to be broken off. The left wing of the Tenth Army stood far to the east, and the Russian cavalry was pressing on it with ever greater force. Field Marshal Paul von Hindenburg ordered a move to winter positions, which Ludendorff chose on the line of lakes between Vishnev, Naroch and Drysviaty. The northern wing of the Tenth Army began to fall back, while fresh reinforcements were joining the Niemen Army from the direction of Lake Drysviaty.

The withdrawal did not go smoothly. According to Ludendorff, the Tenth Army first wanted to halt the advancing Russians, but delayed too long and was badly beaten east of Lake Naroch. “The Russian wave broke against our new front, but the storm gradually died down,” he wrote. He considered the summer campaign against Russia over. He judged the battle a German tactical success that brought no decision, because the manoeuvre had begun too late.

The Russians go over to the defensive

On the Russian side, in the last days of September the new Second Army was driving the Germans out of the area east of Lake Naroch and from the northern bank of the Viliya. By 7 October it had reached a line from Lake Myadel through Naroch to the Viliya and was ordered to “consolidate itself in the area occupied”. Its corps, brought up by forced marches of about 30 kilometres a day, had gone into action straight from the march, without their trains and with little ammunition. Now they were utterly exhausted. The Russian Tenth Army, standing to the south of it, also attacked in several places, but everywhere ran into German trenches and wire. At the beginning of October it halted its attacks. The Russian historian of this operation, Nikolai Evseev, states that, for example, the 1st Guards Infantry Division shrank in eight days of fighting, from 12 to 20 September, from over 10,000 to about 7,000 bayonets.

On the northern wing, by Lake Drysviaty, the Russian First Army was still attacking in October, but without result. On 15 October the commander of the Western Front, General Alexei Evert, proposed to headquarters that for the coming months even partial attacks should be stopped along the whole front, positions strengthened for the winter and the troops brought up to strength. Further north, at Dvinsk, the Niemen Army fought on throughout October for the bridgehead on the Dvina.

A new front line

The battle of Vilna closed the Great Retreat of the Russian army in 1915. The Russians lost Vilna and a large part of the Vilna region, but their armies slipped out of the trap set for them and kept their ability to fight. The Germans, who at the same time were moving divisions to the west and to the Balkans, no longer had the strength to go further. The line from Dvinsk through Lakes Drysviaty and Naroch and Smorgon became a positional front that survived almost unchanged until 1917. Smorgon, lying right by the trench line, was almost completely destroyed over the following years. In the spring of 1916 it was here that the Russians attacked, in the battle of Lake Naroch, and suffered a heavy defeat.