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Xionites
Xionites, Chionites, or Chionitae ( Middle Persian: Xiyon; Avestan: Xiiaona; Sogdian: Xwn; Pahlavi: Huna), or Hunni, Yun or Xūn (獯), were an Iranian-speaking people who were prominent in Transoxania and Bactria.
The Xionites (Chionitae) are first mentioned with Kushans (Cuseni) by Ammianus Marcellinus who spent the winter of 356-57 CE in their Balkh territory. They arrived with the wave of immigration from Central Asia into Iran in late antiquity. They were influenced by the Kushan and Bactrian cultures, while patronizing the Eastern Iranian languages, and became a threat on the northeastern frontier of the Sassanid Empire.