Who defeated the Xiongnu?
Han–Xiongnu War
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In 115 BC Zhang Qian was once again dispatched to the Western Regions to secure military alliances against the Xiongnu.[67][68] He sought out the various states in Central Asia, such as the Wusun.[67] He came back without achieving his goals, but he gained valuable knowledge about the Western Regions like in his previous travels.[68] Emperor Wu received reports from Zhang about the large and powerful horses of Ferghana.[69] These horses were known as "heavenly horses"[69][70] or "blood-sweating horses".[70] Zhang brought back some of these horses to the Han empire.[68] The emperor thought that the horses were of high importance to fight the Xiongnu.[70] The refusal of the Dayuan kingdom, a nation centered in Ferghana, to provide the Han empire with the horses and the execution of a Han envoy led to conflict;[71] the Han forces brought Dayuan into submission in 101 BC.[67][72] The Xiongnu, aware of this predicament, had tried to halt the Han advance, but they were outnumbered and suffered defeat.[73]