Rennenkampf saw combat service in the Boxer Rebellion in 1900 then commanded a cavalry division in the Russo-Japanese War. In the postwar period he led a series of punitive expeditions to put down revolutionary activity in eastern Siberia. Such exploits may have helped compensate for Rennenkampf's less than brilliant service against the Japanese. He was promoted general of cavalry in 1910, by which time he was a corps commander, and, in 1913, he was advanced to take charge of the Vilna Military District.
At the outbreak of World War I Rennenkampf received the Russian First Army, along with orders to participate in his nation's first major wartime offensive in 1914. On August 17 Rennenkampf was to cross the German border, moving westward into East Prussia. He was to be joined in his attack by Samsonov and the Second Army, advancing northward from the Warsaw Military District. Under the coordination of General Zhilinsky, the commander of the northwestern front, the two armies were to pinch off and annihilate the lone German army standing in East Prussia.
The operation was a disaster for which Zhilinsky and Rennenkampf have received varying shares of the blame. Rennenkampf crossed the border on August 17, won easy victories at Stalluponen and Gumbinnen, then slowed to a crawl. By August 23 the Germans were stripping the front facing Rennenkampf, allowing them to use their rail network to fling most of their forces on Samsonov's isolated forces. Zhilinsky failed to push the First Army leader forward; and Rennenkampf, burdened by supply problems, and perhaps none too anxious to "rush" the Germans into a retreat that would prevent Samsonov from cutting them off, never penetrated the thin forces opposite him. The technical weakness of the Russian army intensified the problem. Russian radio transmissions made it clear to the Germans that Rennenkampf posed no threat; because of a lack of trained operators, Russian radio traffic could not be sent in code!
Unlike Zhilinsky, Rennenkampf survived in com¬mand. When the Germans turned on him, he took a heavy toll in the defensive action at the Masurian Lakes in early September, then made a timely retreat. By September 13 he was back over the Russian border. Rutherford suggests, however, that this opportune withdrawal degenerated into a rout. Rennenkampf had one more campaign in him. On November 11 the Germans launched a dangerous attack southeastward from Thorn, cutting between Rennenkampf's First Army facing East Prussia from the south, and the Second Army advancing westward toward Silesia. The ensuing battle of Lodz offered both sides a chance for a great victory.
The Germans lost their chance to smash the Second Army when forces under General Pleve rushed up from the south to help hold Lodz. But Rennenkampf, again slow and hesitant, cost the Russians their opportunity. His First Army came too late to close the trap on the German XXV Reserve Corps, which had curled around to attack Lodz from the east. The Germans escaped, and Rennenkampf found himself unemployed.
His career at an apparent end, Rennenkampf had to defend himself against a commission of inquiry. It was ostensibly directed to look into his purchase of cavalry supplies, which to some eyes seemed indistinguishable from wartime profiteering. But the inquiry clearly took much of its impetus from the cavalryman's dismal combat performance. His court connections saved him from prison, but no more commands were in sight; Rennenkampf retired from military service.
His death came in the form of a last chance to take up a command. After living out most of the war in obscurity, Rennenkampf found himself in southern Russia in early 1918. The Bolsheviks had taken over the government. The final German offensive at the close of February led the Reds to offer charge of an army to Rennenkampf, who was in Taganrog near the Black Sea. He refused, found himself placed immediately on trial, and in early March 1918, Rennenkampf died in front of a Bolshevik firing squad.
Born April 17, 1854
Died April 1, 1918