The Russian Caucasus Army () of World War I was the Russian field army that fought in the Caucasus Campaign and Persian Campaign of World War I. It was renowned for inflicting heavy casualties on the opposing forces of the Ottoman Empire, particularly at the Battle of Sarikamish. It was also known for its extremely diverse ethnic composition, consisting of units from throughout the Russian Empire and both soldiers and officers from the many ethnic communities settled since the 1877-78 Russo-Turkish War in the militarily administered Kars Oblast in the Russian Transcaucasus. These included Georgians, Caucasus Greeks, and Armenians - the latter in particular strongly represented among both the soldiers and senior officers - as well as ethnic Russians and Ukrainians.