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.
List of ancient great powers
The Great Wall of China had been constructed to protect Chinese towns from the Xiongnu attacks. While the Chinese were trying to bring the Xiongnu under control, something of high significance happened: cross-cultural encounters. A large variety of people (such as traders, ambassadors, hostages, parents in cross-cultural marriages, etc.) served as helpers that passed on ideas, values, and techniques across cultural boundary lines. These encounters helped cultures learn from other cultures. Xiongnu empire disintegrated into two parts during the 1st century, eventually the Xiongnu fell due to the defeat in the Han–Xiongnu War.Huns were nomadic people who were known for their hordes of mounted archers. Their language seems to be Turkic; but Mongolic, Yeniseian, Uralic etc., are also postulated. After 370 under a certain Balamber they founded an empire in the East Europe defeating Alans and Goths. They triggered the great migration which eventually caused the collapse of the West Roman Empire.