In 1915, as the Russian Caucasus Army continued to advance into eastern Anatolia, the Ottoman government started the deportation of its ethnic Armenian population, resulting in the death of approximately 1.5 million Armenians in what became known as the Armenian Genocide. The genocide was carried out during and after World War I and implemented in two phases: the wholesale killing of the able-bodied male population through massacre and subjection of army conscripts to forced labour, followed by the deportation of women, children, the elderly and infirm on death marches leading to the Syrian desert. Driven forward by military escorts, the deportees were deprived of food and water and subjected to periodic robbery, rape, and systematic massacre. Large-scale massacres were also committed against the Empire's Greek and Assyrian minorities as part of the same campaign of ethnic cleansing.

When did the Russian Caucasus Army advance into eastern Anatolia?