He was a Baikal Cossack and participant of World War I in the Persian Campaign.
After the fall of the Soviets in Siberia in the summer of 1918 he was one of the founders of the Altagachansky Commune, the nucleus of the Partisan resistance to Grigory Semyonov's troops and the Japanese Expeditionary Corps.
After Pavel Zhuravlev's death he was appointed the commander-in-chief of the Eastern Transbaikalian Front.
At the outbreak of the three operations of retaking Chita all partisan formations were reorganized into regular troops and Korotayev headed the Transbaikal Cavalry Division named after him.
After the Russian Civil War Korotayev served at many military posts.