Sebeos's History 3

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It happened after the death of Hosrov (Խոսրով), son of Kawad (Կաւատ) that his son Ohrmazd (Որմզդ) reigned over all the land of the Persians. His mother, called Qayın (Կայէն), was the daughter of the great Xaqan (Խաքանայ), king of the Yedivar (Թետալացւոց), and the wife of Hosrov, his father. Although very distinguished though his paternal ancestors, he was even more notable and ferocious on his maternal side.

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