JAHBALLĀH III. - Nestorian Katholikos from 1281 to 1317, of Mongol origin, born at Kuösegn in 1244. He lived as a monk in a monastery near Peking. He journeyed to Western Asia on pilgrimage to the Holy Land. He was elected Katholikos of the Nestorian Church to please the Mongol rulers, with whom he thereafter maintained good relations. He sent his former master Rabban Saumā to Rome, who arrived there in 1287. Jahballāh III was on good terms with the Latin missionaries.
BIBL.: J. A. Chabot, L'histoire du patriarche Maré III et du moine Rabban Saumā (translated from the Syriac), in Revue de l'Orient latin, 1 (1893), pp. 573 ff.; 2 (1894), pp. 82-80; E. A. Budge Wallis, The monks of Kābbālī khān, emperor of China, London 1928. Guglielmo de Vries