Nikolai Nikolayevich Yudenich

In January 1916, Yudenich launched one of the most daring operations of the Caucasus Front. With the Gallipoli campaign ending, the Ottoman Empire stood to transfer sixteen divisions to the Caucasus, and Yudenich resolved to strike before enemy reinforcements could arrive. His target was Erzurum: the most formidable fortress-city in eastern Anatolia, defended by eleven forts and 235 guns arranged in two concentric rings covering a 180° arc around the city.

The midwinter offensive caught the Ottoman high command completely off guard. Third Army commander Mahmut Kamil Pasha was in Istanbul, and his chief of staff, Felix Guse, was in Germany. Russian troops advanced through subzero cold and waist-deep snow; the assault on the fortress began on 29 January. The decisive breakthrough came across the Kargapazar Ridge: a mountain spine the Ottomans had dismissed as impassable and left lightly guarded. Once Russian forces crossed it, they enveloped the entire defensive perimeter from the north, and Erzurum fell on 16 February.

The battle effectively destroyed the Ottoman Third Army: 12,988 men were taken prisoner and 323 guns captured. By the end of 1916 the Third Army had been reduced to 36,000 effectives, barely corps strength. For this victory Yudenich received the Order of St. George 2nd Class, the last such award in the history of the Russian Empire, and the fall of Erzurum opened the road deep into Anatolia for the Russian Army.

In December 1914, Ottoman War Minister Enver Pasha took personal command of a bold winter offensive aimed at encircling and destroying the Russian Caucasus Army. Over 90,000 men of the Ottoman Third Army advanced on Sarikamish, with Enver planning a Napoleonic single-envelopment maneuver to drive the Russians into the Aras Valley and annihilate them. But in subzero cold and blizzards, the X Corps lost 90 percent of its strength to frostbite and straggling while crossing the Allahuekber Mountains: it had effectively collapsed before reaching the battlefield.

The Russian high command was equally rattled. Deputy commander General Myshlayevsky and General Bergmann, fearing encirclement, argued for abandoning Sarikamish. Yudenich, then chief of staff, flatly refused. He grasped that the Sarikamish–Kars railway was the army's sole line of retreat and insisted the town be held at all costs. Personally leading Turkestan reserve battalions, he retook Bardız village in a bayonet charge, threatening the Ottoman rear and throwing their attack into disarray.

The Battle of Sarikamish ended on 17 January 1915 with the near-total destruction of the Ottoman Third Army. Of 118,000 men, only 42,000 remained; an estimated 25,000 froze to death in the Allahuekber Mountains before the main engagement even began. Yudenich was promoted to General of Infantry, appointed commander of the Caucasus Army, and awarded the Orders of St. George 4th and 3rd Class. The victory was one of the few decisive Russian successes at a time when the Eastern Front was suffering repeated defeats, and it laid the groundwork for the subsequent advance into Anatolia: to Erzurum, Trebizond, and beyond.

On 28 September 1919, the Northwestern Army under Yudenich's command launched its autumn offensive toward Petrograd. Appointed commander-in-chief by Admiral Kolchak's All-Russian Government and backed by its financial support, Yudenich had assembled a force of roughly 18,500 men, six British-supplied tanks, four armoured trains, and 53 artillery pieces. Within the first week the Whites captured Luga and severed the Pskov–Petrograd railway; Yamburg fell on 12 October. By mid-October Yudenich's forces had taken Gatchina, Krasnoye Selo, Tsarskoye Selo, and Pavlovsk, reaching Pulkovo Heights on the very outskirts of Petrograd.

But a fatal miscalculation undid Yudenich's momentum. The commander of the 3rd Division, Daniil Vetrenko, disobeyed orders to cut the Nikolayevskaya railway line from Moscow to Petrograd at Tosno, leaving the route open for Trotsky's Revolutionary Military Council to rush reinforcements to the city. On 21 October the Red 7th and 15th Armies launched a counter-offensive. Lacking reserves and dangerously overextended, the Northwestern Army was pushed back from Pulkovo. By the end of November Yudenich's forces had been driven to the Estonian frontier, where the Estonian government, negotiating a separate peace with the Bolsheviks, disarmed and interned the remnants of the White army.

Yudenich issued his final order dissolving the Northwestern Army on 22 January 1920. Days later he was arrested by Estonian police and subordinate officers on charges of attempting to abscond with the army's remaining funds, and was freed only after the British and French missions intervened. He departed for exile in France, and the Petrograd offensive ended in decisive White defeat, bringing the organized armed resistance on the northwestern front to a close.