birth is the last mention of Irene in the historical record. By the following year, Constantine was already married to his second wife Maria. Lynda Garland has suggested Tzitzak died in childbirth. References Bibliography Kevin Alan Brook. The Jews of Khazaria. 2nd ed. Rowman & Littlefield Publishers, Inc, 2006. Douglas M. Dunlop. The History of the Jewish Khazars, Princeton, N.J.: Princeton University Press, 1954. The Oxford Dictionary of Byzantium, Oxford University Press, 1991. External links A short article on her by Lynda Garland 8th-century births 750 deaths Deaths in childbirth Khazar people Isaurian dynasty 8th-century Byzantine empresses 740s in the Byzantine Empire 8th-century Turkic women Mothers of Byzantine emperors