First Battle of the Masurian Lakes

First Battle of the Masurian Lakes
Part of the Eastern Front of World War I
Eastern Front to 26 September 1914.
Date 2–16 September 1914 Location East Prussia, Germany (present-day Russia and Poland) Result German victory Russian ejection from East Prussia
Belligerents
Germany	Russian Empire
Commanders and leaders
Paul von Hindenburg Erich Ludendorff August von Mackensen	Paul von Rennenkampf Vasily Flug
Units involved
8th Army	1st Army 10th Army
Strength
Total 244,391 men[1][2] 1,212 guns 400 machine guns	Total 553,937 men[3][4] 1,673 guns 960 machine guns: First army: 306,470 men, 924 guns 395 machine guns Tenth army: 247,467 men 749 guns 565 machine guns
Casualties and losses
German official medical reports (1 - 30.09.1914): 1,555 KIA, 10,412 WIA, 1,552 MIA, Total 13,519[5] Lost:[6] 17 guns 17 machine guns 10,000[7][8] killed, wounded and missing[9][10][11] Other Estimate: 40,000 killed and wounded[12]	100,000[13][14]–125,000 killed, wounded and captured,[15][16][17] Lost:[18] 162 guns 174 machine guns 70,000 killed and wounded,[9] 30,000[19]–45,000 prisoners Russian Estimate: about 60,000 died, wounded and prisoners[20][21] Staff of the Russian NW front: 100,000 men, including 50,000 prisoners[22]

The First Battle of the Masurian Lakes was a German offensive in the Eastern Front 2–16 September 1914, during the Russian invasion of East Prussia. It took place only days after the Battle of Tannenberg where the German Eighth Army encircled and destroyed the Russian Second Army. Using the rapid movements aided by the East Prussian railway network, the Eighth Army reformed in front of the spread-out Russian First Army and pushed them back across their entire front, eventually ejecting it from Germany. Further progress was hampered by the arrival of the Russian Tenth Army on the Germans' right flank.

By the conclusion of the battle, the Imperial German Army had destroyed the Second Army and shattered the First in a series of actions over only a few weeks. However, Russia had the largest army in the world, so the Russian army very quickly restored its losses in manpower, and after a couple of weeks the Russians launched a new offensive in East Prussia.^[23]