Modu Chanyu (234 – 174 BC), a formidable Steppe warrior and chieftain who was in the habit of turning his defeated enemies’ skulls into cups from which he drank blood, unified the nomadic tribes of the eastern Steppe and founded the Xiongnu Empire. Spanning the eastern Steppe from Central Asia to Manchuria, the Xiongnu menaced the Chinese to their south for centuries, forging a complex relationship that alternated between trade and raid, marriage treaties and tribute and war.
In 200 BC, the Chinese emperor Gaozu, founder of the Han dynasty, attempted to bring the Xiongnu to heel but fared even worse than the Persian Darius had with the Scythians. Modu Chanyu led the Chinese invaders on a merry chase through the Steppe, while harrying their supply lines and keeping them on constant edge with frequent skirmishes. When the Chinese were exhausted, Modu ambushed and trapped them in a disadvantageous locale, cut off from resupply and reinforcement.
Surrounded, the Chinese emperor bought his life with an appeasement treaty known as the Heqin, that recognized Modu and the Xiongnu Empire as equals, defined The Great Wall as the mutual border, sent the Xiongnu leaders Chinese princesses as brides, and sought to buy them off with regular tribute payments, face-savingly referred to as “gifts”.
After Gaozu’s death, Modu sent a rude and mocking marriage proposal to his widow, the dowager empress, in 194 BC. Incensed, the empress and court were all for declaring war, with generals urging the extermination of the Xiongnu, until calmer voices reminded everybody of Modu’s victory just a few years earlier, and that the Xiongnu army was more powerful than the Chinese. Reconsidering, the empress wrote back, humbly declining, and sent a gift of imperial carriages and horses.
So badly had Modu beaten the Han emperor, and so memorable was the defeat, that Chinese attempts at a military solution were abandoned, and the Heqin system of buying off the nomads with princesses and tributes became the bedrock of Chinese diplomacy for centuries. The appeasement continued even after the Xiongnu Empire collapsed and the Xiongnu disappeared from the annals of history. Chinese princesses and Chinese “gifts” continued to be sent regularly to Steppe chieftains for over a thousand years, with the last recorded instance of Heqin occurring in 883 AD.