"This individual is sometimes confused with Byzantine Empress Irene, who was her daughter-in-law.
Tzitzak (Greek: Τζιτζάκ) (died c. 750), baptised Irene (Greek: Εἰρήνη), was a Khazar princess, the daughter of khagan Bihar, who became empress by marriage to Eastern Roman Emperor Constantine V (r. 741–775)." - (en.wikipedia.org 11.08.2021)
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