The Germans were continually receiving reinforcements and still largely
outnumbered the Russians. Von Hindenburg therefore determined on a new
assault. The German left wing was now far in front of the Russian city
of Lodz, one of the most important of the Polish cities. The population
was about half a million. Such a place was a constant danger, for it was
the foundation of a Russian salient.

When the German movement began the Russian general, perceiving how
difficult it would have been to hold the city, deliberately withdrew,
and on December 6th the Germans entered Lodz without opposition.

The retreat relieved the Russians of a great embarrassment. Its capture
was considered in Germany as a great German victory, and at this time
von Hindenburg seems to have felt that he had control of the situation.
His movement, to be sure, had not interfered with the Russian advance on
Cracow, but Warsaw must have seemed to him almost in his power. He
therefore concentrated his forces for a blow at Warsaw. His first new
movement was directed at the Russian right wing, which was then north of
the Bzura River and east of Lowicz. He also directed the German forces
in East Prussia to advance and attempted to cut the main railway line
between Warsaw and Petrograd. If this attempt had been successful it
would have been a highly serious matter for the Russians. The Russians,
however, defeated it, and drove the enemy back to the East Prussian
border. The movement against the Russian right wing was more successful,
and the Russians fell back slowly. This was not because they were
defeated in battle, but because the difficult weather interfered with
communications. There had been a thaw, and the whole country was
waterlogged. The Grand Duke was willing that the Germans should fight in
the mud.