 After his return, his knowledge of the lands of the west was the main information the Han had of this region.Between 133 BCE and 89 CE, the Hand and the Xiongnu fought a series of battles, known as the Han–Xiongnu War.In 102 BC the Han defeated Dayuan, who had not been willing to supply the Han with Ferghana horses, in the War of the Heavenly Horses.