Yuezhi

The Yuezhi were a nomadic people who lived in what is now Gansu, in north-western China, in the first millennium BCE. Driven west by the Xiongnu in the second century BCE, they migrated thousands of kilometres across Central Asia, and one of their branches later founded the Kushan Empire.

Chinese sources describe the Yuezhi as a powerful nomadic people, with perhaps 100,000 to 200,000 archers, living between Dunhuang and the Qilian mountains. They traded jade from Khotan to China, and some scholars link them to the Xiaohe and Tarim Basin mummies, though this is uncertain. In the third century BCE, the Yuezhi were stronger than the Xiongnu, who sent the young Modu as a hostage to them.

After Modu became chanyu of the Xiongnu in 209 BCE, he attacked the Yuezhi. Around 176 BCE, according to a letter from Modu to the Han emperor, the Xiongnu defeated them. According to the historian Sima Qian, Modu's son Laoshang killed the Yuezhi king and made a drinking cup from his skull, a story that may reflect steppe customs.

Most of the Yuezhi, the Greater Yuezhi, moved west to the Ili valley, displacing the Saka, Scythian peoples who moved south into Bactria and India. Then the Wusun, allies of the Xiongnu, attacked the Yuezhi and pushed them further, south-west to the valley of the Oxus river, the Amu Darya. A smaller group, the Lesser Yuezhi, stayed in the Qilian mountains among the Qiang peoples.

Around 138 BCE the Han emperor Wu sent the envoy Zhang Qian to find the Yuezhi and persuade them to join an alliance against the Xiongnu. Zhang was captured by the Xiongnu and held for about ten years, during which he married a Xiongnu wife. He escaped and travelled through Ferghana and Sogdiana and reached the Yuezhi, who by then lived north of the Oxus and had made Bactria their vassal. The Yuezhi, settled in a rich land, declined the alliance. Zhang returned to China in 126 BCE and reported to the emperor on Central Asia, the "heavenly horses" of Ferghana, and lands such as Parthia and India. His journey helped open the Silk Road.

Bactria, in today's northern Afghanistan, had been ruled by Greek kings, descendants of Alexander's soldiers, since the third century BCE, with cities such as Ai-Khanoum, which was destroyed around 145 BCE, perhaps by the Saka or Yuezhi. The Yuezhi took over the region around 130 BCE, divided it among five chiefs, xihou, or yabgus, and adopted aspects of Greek and Bactrian culture, including coinage. The rich burials at Tillya Tepe, in northern Afghanistan, from the first century BCE, with thousands of gold objects, may belong to Yuezhi or Saka nobles.

In the first century CE, Kujula Kadphises, chief of the Guishuang, or Kushan, one of the five Yuezhi tribes, united the others and expanded across the Hindu Kush into Gandhara and India, founding the Kushan Empire. Chinese sources continued to call the Kushans the Yuezhi.

Many scholars identify the Yuezhi with the Tocharians, speakers of Indo-European languages, Tocharian A and B, known from Buddhist manuscripts of the sixth to eighth centuries found in the Tarim basin. Others reject or question the link. The origins and language of the Yuezhi remain debated.

Our maps show the Yuezhi on the 200 and 100 BCE maps. Their largest outline, about 2.8 million square kilometres on the 100 BCE map, stretches across today's Pakistan, India and Afghanistan, which suggests that the basemap groups other peoples, such as the Indo-Scythians, with them. Kabul, Samarkand and Lahore lie inside it on that map. Their successor on our maps is the Kushan Empire.