Eastern Orthodox

Pulcheria, fifth-century empress of the Eastern Roman Empire, helped shape Christian doctrine at the Council of Chalcedon in 451 CE.

The story of Olga of Kiev, the first Christian ruler of Kievan Rus', whose private conviction became the foundation of a civilization's transformation.

Symeon the New Theologian saw the uncreated light of God and refused to call it anything softer --- and history had to catch up with him.