Anastasia Romanovna Zakharyina-Yurieva (1530 – 7 August 1560) was the first wife of the Russian Tsar Ivan the Terrible and the first Russian tsaritsa. She was the daughter of Boyar Roman Yurievich Zakharyin-Yuriev, Okolnichi, who died on 16 February 1543, who gave his name to the Romanov Dynasty of Russian monarchs, and wife Uliana Ivanovna, who died in 1579.

She was selected as the best bride for Ivan from a large number of suitable mates, brought to the Kremlin specifically for the selection process. All the noble families throughout Russia were given an invitation to present their eligible daughters for this purpose (it is said that there were between 500 and 1500 girls to choose from). Anastasia and Ivan's marriage took place on 3 February 1547 at the Cathedral of the Annunciation. She gave birth to a total of six children (Anna, Maria, Dmitry, Ivan, Eudoxia, and Feodor).

It is widely believed that Anastasia had a moderating influence on Ivan's volatile character. In the summer of 1560, she fell ill to a lingering illness. In consequence to these events, Ivan suffered a severe emotional collapse suspecting that his wife had been a victim of malicious actions and had been poisoned by the Boyars. Although he had no evidence of such crimes, he had a number of them tortured and executed. He had already had a strong dislike for the Boyars due to their abusive actions toward him during his childhood.

Further examination of the bone remains of Anastasia in the late 20th century by archaeologists and forensics experts have been able to provide evidence that could actually sustain her husband's claim. The high levels of mercury in her hair could be symptomatic of poisoning. However mercury was also used as a cure, and so this is disputed.

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