Battle of Tannenberg

The Russian plan of attack for the battle involved consolidating the forces of the 1st and 2nd Armies in order to encircle and overwhelm the German Eight Army, which was originally under the command of Gen. Prittwitz. Rennenkampf’s 2nd Army would attack the German front, while Samsonov hit the German rear. The plan began to unravel when Gen. Rennenkampf delayed his advance after successfully engaging German forces at the Battle of Gumbinnen on 20 August 1914. Poor communications between the Russian Armies mislead Gen. Samsonov to believe that Rennenkampf’s forces were moving south-west as planned. As a result, Samsonov soon found himself facing several German divisions by himself. The German forces quickly encircled the Russian 2nd Army and nearly 100,000 Russians were killed or captured.
Causes of the battle. On 17 August 1914, two Russian Armies invaded East Prussia in order to conduct a two-pronged assault on German forces in accordance with Plan 19. This was Russia’s pre-...