the Ilkhanate, where they were welcomed by Patriarch Denha I of the Church of the East. The Patriarch requested the two monks to visit the court of the Mongol Ilkhanate ruler Abaqa Khan, to obtain confirmation letters for Mar Denha's ordination as Patriarch in 1266. During the journey, Rabban Markos was declared a "Nestorian" bishop. The Patriarch then attempted to send the monks as messengers back to China, but military conflict along the route delayed their departure, and they remained in Baghdad. When the Patriarch died, Rabban Markos was elected as his replacement, Yahballaha III, in 1281. The two monks traveled to Maragheh to have the selection confirmed by Abaqa, but the Ilkhanate khan died before their arrival, and was succeeded by his son, Arghun. It was Arghun's desire to form a strategic Franco-Mongol alliance with the Christian Europeans against their common enemy, the Muslim Mamluk Sultanate at Cairo. A few years later, the new patriarch Yahballaha III suggested his former teacher Rabban Bar Ṣawma for the embassy, to meet with the Pope and the European monarchs. Ambassador to Europe In 1287, the elderly Bar Sauma embarked on his journey to Europe, bearing gifts and letters from Arghun to the Eastern Roman emperor, the Pope, and the European kings. He followed the embassy of another "Nestorian", Isa Kelemechi, sent by Arghun to Pope Honorius IV, in 1285. Rabban Bar Sauma traveled with a large retinue of assistants, and 30 riding animals. Companions included the Church of the East Christian (archaon) Sabadinus; Thomas de Anfusis (or Tommaso d'Anfossi), who helped as interpreter and was also a member of a famous Genoese banking company; and an Italian interpreter named Uguetus or Ugeto (Ughetto). Bar Sauma likely did not speak any European languages, though he was known to be fluent in Chinese, Turkic, and Persian, and he was able to read Syriac. Europeans communicated to him in Persian. He traveled overland through Armenia to either the Empire of Trebizond or through the Sultanate of Rum to the Simisso on the Black Sea, then by boat to Constantinople, where he had an audience with Andronicus II Palaeologus. Bar Sauma's writings give a particularly enthusiastic description of the beautiful Hagia Sophia. He next traveled to Italy, again journeying by ship. As their course took them past the island of Sicily, he witnessed and recorded the great eruption of Mount Etna on 18 June 1287. A