The flag of the Georgian Orthodox Church, the red St. Nino's cross is depicted boldly on the flag of the nation of which she is the patron saint. The shade of red in the cross is darker than that of the national flag, and is edged with white and blue.

St. Nino (or Nina, c. 300 - 332) is known as the Enlightener of Georgia. One of the most venerated saints of the Georgian Orthodox Church, Nino is said to have been a relative of St. George; she converted different rulers so that King Mirian III (c. 284 - c. 361) of Iberia (today's Kartli) adopted Christianity as the official religion c. 327.

The St. Nino's cross, also known as the Grapevine cross, is the main symbol of the Georgian Orthodox Church. Holy tradition teaches that Nino either received it from the Mother of God, or crafted it herself with two grapevine branches entwined with her own hair. During Persian and Turkish invasions, the holy cross was hidden in Armenia, in the Georgian mountains, and, eventually in Moscow. Upon request of Prince George Bagration, Tsar Alexander I returned the cross to Georgia in 1802. Since then, the cross has been preserved in the Sioni Cathedral in Tbilisi.

‍Saint Nina is commemorated on January 14/27.

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