Transoxania and the Khazakh Steppe
Something of a misnomer, since parts of Khazakhstan border the edge of Europe between the Caspian and the Urals, this region is nevertheless very central to Eurasia as a whole. A vast semi-arid land, in part steppe or desert and in part some of the highest mountains in the world, Central Asia has been the crossroads between the Far East and Far West for as long as there have been humans. This was the central portion of the Silk Road, here are the famous caravan cities of Samarkand and Tashkent, and here saw the "Great Game" between Russia and Great Britain in the 19th century.
Currently I have: Aryani and Aryanam-Baydjo, Astrakhan, Bokhara, Chorasmia, the Dahae, the Haraiva, the Kangui, the Karluks, Khazakhstan, Khiva, Khokand (Farghana), Khwarazm, Kyrgyzstan, Margiana, Otrar, Qarakalpak, Samarkand, Sogdiana, Tashkent, Transoxania, Turkmenistan, Usrushana, Uzbekistan, and the Yue-Zhi.