Olga of Kiev

Olga was a regent of Kievan Rus' for her son Sviatoslav from 945 until 960. Following her baptism, Olga took the name Elenа. She is known for her subjugation of the Drevlians, a tribe that had killed her husband Igor of Kiev. Even though it would be her grandson Vladimir that would convert the entire nation to Christianity, because of her efforts to spread Christianity through Rus', Olga is venerated as a saint in the Eastern Orthodox Church with the epithet "Equal to the Apostles" and her feast day is 11 July.