Giyorgis of Segla

Abba Giyorgis of Segla (c. 1365–1425) was one of the most influential Ethiopian Orthodox theologians and Ge'ez writers of his age. He served as court chaplain to Emperor Dawit I and tutored royal princes.

His teaching on the Sabbath drew the hostility of Dawit I, who imprisoned him. He was released on the accession of Tewodros I and later flourished under Yeshaq I.

His best-known works are the Book of Hours (Sa'atat) and the theological treatise Book of the Mystery of Heaven and Earth, which shaped Ethiopian liturgy and calendars.