Following the defeat of the Russian Second Amy at Tannenberg, the German Eighth Army turned its attention back to the First Army. Reinforced with two corps and an independent division from the Western Front, Hindeñburg rushed his troops eastward to push the Russians off every inch of German soil rather than strike south to finish off Second Army. But the Russians had brought forward reinforcements of their own, with the new Tenth Army taking the field south of First Army's lines.

As the vanguard of III Siberian Corps and Tenth Army, the Finnish riflemen had been expected to hold their ground to allow those formations to deploy in front of the German advance. But the German Landwehr, gaining great confidence after their successes at Tannenberg, would not be denied. They pushed the troops many considered the Russian Army's best regular infantry out of the town of Bialla, beginning what would be known as the First Battle of the Masurian Lakes.