Ricoldo of Montecroce

Riccoldo da Monte di Croce or Ricoldo of Monte Croce (Pennini, that is "son of Pennino"; Latin: Ricoldus de Monte Crucis), c. 1243 – 1320, was an Italian Dominican monk, travel writer, missionary, and Christian apologist.

Riccoldo was born in Florence, and his family name originated from a small castle just above Pontassieve. After studying in various major European schools, he became a Dominican in 1267, entering the house of Santa Maria Novella. He was a professor in several convents of Tuscany, including St Catherine in Pisa (1272–99). With a papal commission to preach he departed for Acre (Antiochia Ptolemais) in 1286 or 1287 and made a pilgrimage to the Holy Land (1288) and then travelled for many years as a missionary in western Asia. He arrived in Mossul in 1289, equipped with a Papal bull. He failed to convince the Nestorian Christian mayor of the city to convert to Catholicism. He was a missionary to the court of the Mongol Il-Khan ruler Arghun, of whom he wrote that he was "a man given to the worst of villainy, but for all that a friend of the Christians".

Moving to Baghdad, Riccoldo entered in conflict with the local Nestorian Christians, preaching against them in their own cathedral. He was allowed nonetheless by Mongol authorities to build his own church, with the interdiction to preach in public. Riccoldo brought the matter to the Nestorian patriarch Mar Yaballaha, who agreed with him that the doctrine of Nestorius, namely the duality of Christ (thus achieving a theoretical fusion of the Latin Church and the Church of the East) was heretical. Mar Yaballaha was however disavowed by his own followers.

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