Venerable Hilarion the Georgian (Kartveli), of Mount Olympus and Thessaloniki

Venerable Hilarion was born around 816-823 in Kakheti (Eastern Georgia) into the princely Vachnadze (Donauri) family. At age 12 he took monastic vows at a monastery founded by his father; at 16 he moved to the Davit-Gareja lavra, where he spent a decade of ascetic life; he was ordained priest but declined an offered bishopric. He spent 17 years as a hermit near the Jordan River (in a cave associated with the Prophet Elijah and John the Baptist).

After his father's death he returned to Georgia, distributed his inheritance, and set out for Constantinople. Around 864 he founded a Georgian monastery on Mount Olympus in Bithynia, where he spent about 5 years, becoming renowned for numerous healings; then, seeking anonymity, he traveled via Rome to Thessaloniki, where he spent the last 3 years of his life. He died on November 19, 875. In 882 Emperor Basil I translated his relics to Constantinople. He was canonized by the Georgian Church in the 9th century.

IMPORTANT CLARIFICATION: claims that Venerable Hilarion was a disciple of St. Euthymius the Athonite are not confirmed — Euthymius the Athonite (955-1028) lived roughly 150 years after Hilarion's death (†875), making such discipleship chronologically impossible. He is also not the same person as the entry "Hilarion of Iveron" (hilarion_of_iveron): Venerable Hilarion Kartveli lived and died a century before the founding of Iveron Monastery (980-983) and has no connection to it.