Song Yun or Songyun (fl. 510s & 520s) was a Chinese Buddhist monk who travelled to medieval India from the Tuoba Northern Wei kingdom during China's Northern and Southern dynastic period at the behest of the Empress Hu. He and his companions Huisheng, Fali, and Zheng or Wang Fouze left the Wei capital Luoyang on foot in 518 and returned in the winter of 522 with 170 Buddhist scriptures. Song and Hui's accounts of their journey are now lost but much of their information was preserved in other texts.
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Song Yun in the context of Mihirakula
Mihirakula (Gupta script: 
, Mi-hi-ra-ku-la, Chinese: 摩酰逻矩罗 Mo-hi-lo-kiu-lo), sometimes referred to as Mihiragula or Mahiragula, was the second and last Alchon Hun king of northwestern region of the Indian subcontinent between 502 and 530 CE. He was a son of and successor to Toramana of Huna heritage. His father ruled the Indian part of the Hephthalite Empire. Mihirakula ruled from his capital of Sagala (modern-day Sialkot, Pakistan).
In around 520 CE, the Chinese monk Song Yun met with Mihirakula. According to the 7th-century travelogue of the Chinese Buddhist pilgrim and student Xuanzang, Mihirakula ruled several hundreds of years before his visit, was initially interested in Buddhism, and sought a Buddhist teacher from monasteries in his domain. They did not send him a learned Buddhist scholar. Feeling insulted, he became anti-Buddhist and destroyed the monasteries in his kingdom.
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