Soviet Central Asia is the era from the 1917 revolution to the Soviet collapse in 1991, when the Russian-ruled steppe and oases of Turkestan were reorganized, in stages, into five national republics: Uzbek and Turkmen in 1924, Tajik by 1929, Kazakh and Kyrgyz only in 1936. Collectivization fell unevenly, making cotton belts of Uzbekistan, Turkmenistan, and parts of Tajikistan while the Kazakh and Kyrgyz lands centered on herding, grain, and mining; on the Kazakh steppe forced sedentarization brought a famine that killed roughly 1.5 million, near a third of the Kazakh people. In 1991 the five emerged as independent states carrying Soviet borders and economies.
In the mid-1920s Soviet planners sat down and drew national republics onto a region that had never been divided that way. The lines they inked — Uzbek here, Kazakh there, Tajik in the mountains — still run today as the international borders of five countries. The Soviet state did not invent these peoples from nothing, for their languages and communities were real, but it fixed fluid identities into hard nations, each with a border, a capital, and an official past, and the nations it institutionalized would long outlive it.