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 The Central Powers planned four offensives on their Eastern Front in early 1915. The Germans, led by Supreme Commander of All German Forces in the East Paul von Hindenburg, would attack eastward from their front line in western Poland, which had been occupied after the Battle of Łódź in 1914, toward the Vistula River and also in East Prussia in the vicinity of the Masurian Lakes (site of the 1914 Battle of the Masurian Lakes). The Austro-Hungarians would emerge from the Carpathian Mountain passes to attack the Russians by driving toward Lemberg. They would be led by General Alexander von Linsingen. Further south General Borojevic von Bojna would attempt to relieve the besieged fortress at Przemyśl. According to Prit Buttar, "It was with considerable reluctance that Falkenhayn agreed to the deployment of four additional corps on the Eastern Front in early 1915. Whilst he remained convinced of the primacy of the Western Front, the failure to win a decisive victory there left him unable to counter the arguments of Hindenburg and Ludendorff...might be able to inflict a sufficiently heavy defeat upon Russia to end the conflict in the east." Ludendorff wrote, "It was agreed with OHL to use the four corps to strike against the enemy forces deployed against Eighth Army as soon as they arrived. The experiences of Tannenberg and the Battle of the Masurian Lakes had shown that a great and swift victory in battle could be achieved if the enemy were attacked from two sides." Ludendorff's target for the German attack was the Russian Tenth Army, with a northern thrust from Tilsit through Wladislawow to Kalvarija, and a southern thrust from the Spirding-See near Bialla to Raigrod and then to Augustowo. The Russians were to be held in position by a frontal attack, and if successful, Ludendorff planned further attacks on Osowiec and Grodno. The German northern thrust was to be made by the newly formed Tenth Army, under the command of Eichhorn, with the XXI Corps, XXXIX Reserve Corps, and XXXVIII Reserve Corps deployed from the Niemen River to Insterburg. Landwehr formations