area of the Ili river, to the northwest of Kucha. Chinese official and diplomat Zhang Qian traveled the area westward to visit Central Asia, during the 2nd century BCE, stopping at Kucha. The Roman Maes Titianus visited the area of Kucha in the 2nd century CE. According to the Book of Han (completed in 111 CE), Kucha was the largest of the "Thirty-six Kingdoms of the Western Regions", with a population of 81,317, including 21,076 persons able to bear arms. The Kingdom of Kucha occupied a strategic position on the Northern Silk Road, which brought prosperity, and made Kucha a wealthy center of trade and culture. Han-Xiongnu contention During the Later Han (25–220 CE), Kucha, with the whole Tarim Basin, became a focus of rivalry between the Xiong-nu to the north and the Chinese to the east. In 74 CE, Chinese troops started to take control of the Tarim Basin with the conquest of Turfan. During the 1st century CE, Kucha resisted the Chinese invasion, and allied itself with the Xiong-nu and the Yuezhi against the Chinese general Ban Chao. Even the Kushan Empire of Kujula Kadphises sent an army to the Tarim Basin to support Kucha, but they retreated after minor encounters. Chinese conquest In 124, Kucha formally submitted to the Chinese court, and by 127 China had conquered the whole of the Tarim Basin. Kucha became a part of the Western protectorate of the Chinese Han Dynasty, with China's control of the Silk Road facilitating the exchange of art and the propagation of Buddhism from Central Asia. The Roman Maes Titianus visited the area in the 2nd century CE, as did numerous great Buddhist missionaries such as the Parthian An Shigao, the Yuezhis Lokaksema and Zhi Qian, or the Indian Chu Sho-fu (竺朔佛). Around 150 CE, Chinese power in the western territories receded, and the Tarim Basin and its city-states regained independence. 4th and 5th century Silk Road Kucha became very powerful and rich in the last quarter of the 4th century CE, about to take over most of the trade along the Silk Road at the expense of the Southern Silk Road, which lay along the southern edge of the Tarim Basin. According to the Jinshu, Kucha was highly fortified, had a splendid royal palace, as well as many Buddhist stupas and temples: Culture flourished, and Indian Sanskrit scriptures were being translated by the Kuchean monk and