campaigns had a significant influence on a tribal leader's prestige. In the 6th century the Göktürk Khaganate consolidated their dominance over the northern steppe region through a series of military victories against the Shiwei, Khitan, Rouran, Tuyuhun, Karakhoja and Yada. By the end of the 6th century, following the Göktürk civil war, the short-lived empire had split into the Eastern and Western Turkic Khaganates, before it was conquered by the Tang in 630 and 657, respectively. Nomadism persists in the steppe lands, though it has generally been disapproved of by modern regimes, who have often discouraged it with varying degrees of coercion. Chronological division Chronologically, there have been several "waves" of invasions of either Europe, the Near East, India and China from the steppe. Bronze Age Proto-Indo-Europeans (see Indo-European migrations), Kurgan theory and the later Indo-Aryan migration Iron AgeClassical Antiquity Iranian peoples; Late Antiquity and Migration period Early Middle Ages Turkic expansion, Magyar invasion; High Middle Ages to Early Modern period Mongol Empire and continued Turkic expansion; See also Eurasiatic languages Inner Asia Nomadic empire Steppe Route Lev Gumilyov By region Nomadic peoples of Europe Nomads of India References Bibliography Amitai, Reuven; Biran, Michal (editors). Mongols, Turks, and others: Eurasian nomads and the sedentary world (Brill's Inner Asian Library, 11). Leiden: Brill, 2005 (). Drews, Robert. Early riders: The beginnings of mounted warfare in Asia and Europe. N.Y.: Routledge, 2004 (). Golden, Peter B. Nomads and their neighbours in the Russian Steppe: Turks, Khazars and Qipchaqs (Variorum Collected Studies). Aldershot: Ashgate, 2003 (). Hildinger, Erik. Warriors of the steppe: A military history of Central Asia, 500 B.C. to A.D. 1700. New York: Sarpedon Publishers, 1997 (hardcover, ); Cambridge, MA: Da Capo Press, 2001(paperback, ). Kradin, Nikolay. 2004. Nomadic Empires in Evolutionary Perspective. In Alternatives of Social Evolution. Ed. by N.N. Kradin, A.V. Korotayev, Dmitri Bondarenko, V. de Munck, and P.K. Wason (p. 274–288). Vladivostok: Far Eastern Branch of the Russian Academy of Sciences; reprinted in: The Early State, Its Alternatives and Analogues. Ed. by Leonid Grinin et al. (р. 501–524). Volgograd: Uchitel'. Kradin, Nikolay N. 2002. Nomadism, Evolution, and World-Systems: Pastoral Societies in Theories of Historical Development. Journal of World-System Research 8: 368–388. *Kradin, Nikolay. 2003. Nomadic Empires: Origins, Rise, Decline. In Nomadic Pathways in Social Evolution. Ed. by N.N. Kradin, Dmitri Bondarenko, and T. Barfield (p. 73–87). Moscow: Center for Civilizational Studies, Russian Academy of Sciences. *Kradin, Nikolay. 2006.