History of Mongolia
Although the Xiongnu finally had been split into two parts in AD 48, the Xianbei (or Hsien-pei in Wade–Giles) had moved (apparently from the east) into the region vacated by the Xiongnu. The Xianbei were the northern branch of the Donghu (or Tung Hu, the Eastern Hu), a proto-Mongol group mentioned in Chinese histories as existing as early as the 4th century BC. The language of the Donghu is believed to be proto-Mongolic to modern scholars. The Donghu were among the first peoples conquered by the Xiongnu. Once the Xiongnu state weakened, however, the Donghu rebelled. By the 1st century AD, two major subdivisions of the Donghu had developed: the proto-Mongolic Xianbei in the north and the Wuhuan in the south.
History of Siberia
As early as the first millennium BCE, trade was underway over the Silk Road. Silk goods were imported and traded in Siberia.
The establishment of the Xiongnu empire in the 3rd century BCE started a series of population movements. Many people were probably driven to the northern borders of the great Central Siberian Plateau. Turkic people such as the Yenisei Kirghiz had already been present in the Sayan region. Various Turkic tribes such as the Khaka and Uyghur migrated northwestwards from their former seats and subdued the Ugric people.