During the Han Dynasty (206 BCE–220 CE), substantial numbers of Han Chinese lived in the Xining valley to the east. In the 17th century, Mongolic-speaking Oirat and Khalkha tribals migrated to Qinghai and became known as Qinghai Mongols. In 1724, the Qinghai Mongols led by revolted against the Qing Dynasty. The Yongzheng Emperor, after putting down the rebellion, stripped away Qinghai's autonomy and imposed direct rule. Although some Tibetans lived around the lake, the Qing maintained an administrative division from the time of Güshi Khan between the Dalai Lama's western realm (slightly smaller than the current Tibet Autonomous Region) and the Tibetan-inhabited areas in the east. Yongzheng also sent Manchu and Han settlers to dilute the Mongols.