Second Battle of the Masurian Lakes

The Second Battle of the Masurian Lakes, also known as the Winter Battle of the Masurian Lakes, was the northern part of the Central Powers' offensive on the Eastern Front in the winter of 1915. The offensive was intended to advance beyond the Vistula River and perhaps knock Russia out of the war.

Background
German Chief of Staff Erich von Falkenhayn strongly believed that the war was going to be won on the Western Front and was hesitant to lend support to Paul von Hindenburg, commander of the Eastern Front. However Falkenhayn did eventually sanction Hindenburg's planned offensive.

Hindenburg would personally lead the northern offensive in the area of the Masurian Lakes (site of the 1914 Battle of the Masurian Lakes). General Alexander von Linsingen would lead an attack against the Russians in the Carpathians aimed at Lemberg, and further south General Borojevic von Bojna would attempt to relieve the besieged fortress at Przemysl.

Forces
Hindenburg had available for the northern offensive the German Eighth Army, commanded by Otto von Below. A newly created force, the German Tenth Army, commanded by Colonel-General Hermann von Eichhorn was also being sent to the east. Facing Hindenburg was General Sievers' Russian Tenth Army in the area of the Masurian Lakes. To the south along the Russian line near the Masurian Lakes was the Russian Twelfth Army under Pavel Plehve.

Battle
On the February 7, in the middle of a snowstorm, Below's Eighth Army launched a surprise attack against Sievers and advanced 70 miles within the week, inflicting severe casualties on the Russians. The Russian withdrawal was disorderly and many of them were taken prisoner. The greatest loss came when the Russian 20th Army Corps, under General Bulgakov, had become surrounded by the German Tenth Army in the Augustow Forest. On February 21 the entire corps surrendered.

Even though the Russians had lost an entire corps, its heroic stand had enabled the rest of the Russian Tenth Army to form a new defensive position. On February 22, the next day, Plehve's Russian Twelfth Army counterattacked and checked the German advance. The counterattack ended any further German advances and brought the battle to an end.

Outcome
The Second Battle of Masurian Lakes ended the German offensive in the north. The Russians had suffered severe losses of soldiers and ground, but they had prevented the Germans from advancing far into Russia. Germany had also failed to come close to knocking Russia out of the war.

Further south, Alexander von Linsingen's offensive had failed with severe losses, and the fortress at Przemysl had been forced to surrender to the Russians. Overall the Austro-Hungarian–German offensive of 1915 had failed to achieve its major objectives. The German high command ended operations in which Germans operated as an independent force, supporting Austrian campaigns in the south. From this point onwards in the war, Germany and Austria-Hungary functioned under joint operations on the Eastern Front.