Han dynasty
To the north of China proper, the nomadic Xiongnu chieftain Modu Chanyu (r. 209–174 BC) conquered various tribes inhabiting the eastern portion of the Eurasian Steppe. By the end of his reign, he controlled Manchuria, Mongolia, and the Tarim Basin, subjugating over twenty states east of Samarkand. Emperor Gaozu was troubled about the abundant Han-manufactured iron weapons traded to the Xiongnu along the northern borders, and he established a trade embargo against the group. In retaliation, the Xiongnu invaded what is now Shanxi province, where they defeated the Han forces at Baideng in 200 BC. After negotiations, the "heqin" agreement in 198 BC nominally held the leaders of the Xiongnu and the Han as equal partners in a royal marriage alliance, but the Han were forced to send large amounts of tribute items such as silk clothes, food, and wine to the Xiongnu.
History of Tuva
The Xiongnu ruled over the area of Tuva prior to 200 AD. The identity of the ethnic core of Xiongnu has been a subject of varied hypotheses and proposals by scholars including Mongolic and Turkic. At this time a people known to the Chinese as Dingling inhabited the region. The Chinese recorded the existence of a tribe of Dingling origin named "Dubo" in the eastern Sayans. This name is recognized as being associated with the Tuvan people and is the earliest written record of them. The Xianbei defeated the Xiongnu and they in turn were defeated by the Rouran. From around the end of the 6th century, the Göktürks held dominion over Tuva up until the 8th century when the Uyghurs took over.