The Göktürks or Kök-Türks were a Turkic people of ancient North and Central Asia and northwestern China. Under the leadership of Bumin Khan and his sons they established the first known Turkic state around 546, taking the place of the earlier Xiongnu as the main power in the region. They were the first Turkic tribe to use the name "Türk" as a political name. The empire was split into a western and an eastern part around 600 and was conquered by the Tang Dynasty, but merged again in 680, and finally declined after 734 following the establishment of Uyghur Khaganate.