The Semirechye Cossask Host was created out of a part of the Siberian Cossack Host in 1867. It was headed by a nakazny ataman (who was the military governor of the oblast, at the same time), subordinated to the Governor General of the Steppe, starting in 1882, and later to the Governor General of Turkestan, starting in 1899.
In the early 20th century, the Semirechye Cossask Host supplied 1 cavalry regiment (4 sotnyas) and 1 platoon of guards in times of peace. In times of war, it supplied 3 cavalry regiments and 12 detached sotnyas. The Semirechye Cossasks possessed 7,440 km² of land, including 710 km² of arable land. In 1916, The Cossack population in this region equaled approximately 45,000 people.
The Semirechye Cossask Host supported the colonial policy of the Tsar in Kyrgyzstan and Kazakhstan, took part in conquering Central Asia and in World War I. During the Russian Civil War, the prosperous leadership of the Semirechye Cossask Host opposed the Soviets. After the defeat of the White movement in the Seven Rivers region (Semirechye) in April of 1920, the Semirechye Cossask Host disbanded. As part of the process of "Decossackization", its former members were forcibly transferred to the Russian Extreme North.