The Battle of Köprüköy was a major engagement of the Caucasus Campaign during World War I. Occurring between January 10 and 19, 1916, it resulted in a decisive victory for the Russian Empire and broke the Ottoman defensive lines protecting Erzurum.
The Ottoman Third Army's defensive front was divided into three distinct sectors. The central sector, considered the most critical, stretched from the Cakir-baba ridge to the Aras river south of Azapköy, covering the primary road to Erzurum through the Pasin valley.[1]:332
The Russian command, led by Nikolai Yudenich, studied these positions in detail. While the Ottoman line was well-fortified with wire and artillery, it suffered from a critical lack of reserves to address a concentrated breakthrough.[1]:333
Yudenich opted to strike at the boundary between the northern and central sectors near the Cakir-baba ridge, positioning the 4th Caucasian Rifle Division to spearhead the offensive.[1]:334 Following a series of diversionary attacks on January 10 that forced the Ottoman command to misallocate the 17th Division,[1]:337 the main Russian assault began on January 14 near the Cakir-baba ridge.[1]:340
Despite heavy snow and determined resistance, the Russian forces reached the point of breakthrough by January 15. The Siberian Cossacks were deployed to the sector to exploit the gaps in the line.[1]:340–341 Facing encirclement, Abdul Kerim Pasha ordered a general withdrawal on the night of January 16–17. The Siberian Cossacks successfully annihilated the Ottoman rear-guard, though the bulk of the Third Army managed to retreat to the Erzurum fortress system.[1]:341
The Ottoman Third Army suffered 25,000 total casualties (killed, wounded, and frozen), while Russian losses reached 12,000, including significant numbers of frostbite cases.[1]:342 The victory allowed Russia to threaten Erzurum directly, fundamentally altering the strategic situation in the Caucasus.[1]:342