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Brusilov Offensive

In the spring of 1916, the Central Powers experienced a military catastrophe in the East that left Germany bearing much of the war effort until the end of hostilities. On 4 June, the Russian Army began a massive offensive along 480 km (300 mi) of the southwestern front in present-day western Ukraine. In the ensuing onslaught, four armies commanded by General Aleksei Brusilov overwhelmed entrenchments that the Austro-Hungarians long regarded as impregnable. Probing assault troops located three weak spots which then were struck in force. In nine days they captured more than 200,000 men and 200 guns and pushed into the open country.

Under Hindenburg's command, Ober Ost desperately shored up weak points with soldiers stripped from less threatened positions. Ludendorff was so distraught on the phone to OHL that General Wilhelm Groener (who directed the army's railroads and had been a competitor with Ludendorff on the General Staff) was sent to evaluate his nerves, which were judged satisfactory. For a week the Russians kept attacking: they lost 80,000 men; the defenders 16,000. On 16 July the Russians attacked the German lines west of Riga but were ultimately thwarted. When looking back on the Russian offensive, Hindenburg admitted that another attack of such scale and ferocity would have left his forces "faced with the menace of a complete collapse."