1 Answers
Rainier was an Italian cleric who served as the vice-chancellor of the Roman church from 1216 until 1219 and the Latin patriarch of Antioch from 1219 until his death.
Nothing much of Rainier's early life is known. He is described as coming from the castle called Castrum Vetus in the county of Todi in the papal document confirming him as patriarch. He probably received a formal education, most likely in law. He is described by Pope Honorius III as a "man of knowledge" and a document of 1215 may indicate that he had a university degree.
Before becoming vice-chancellor, Rainier was the prior of the basilica of San Frediano in Lucca, a community of canons regular. He may have been a canon regular himself, but more likely the posting was a sinecure. He probably served in the Roman chancery for some time before his appointment as vice-chancellor. Possibly he met the future Honorius III when the latter was vice-chancellor in 1194–1197, since he became vice-chancellor in 1216 shortly after Honorius III's election as pope. A document of 1215 refers to an apostolic notary called Master Rainier, which may be the future patriarch.
Rainier was consecrated patriarch of Antioch in November 1219. He replaced Peter of Capua, Honorius' previous nominee, who was being promoted to a cardinalate. The pope informed the Antiochene chapter of the change in a letter of December. At Antioch, Rainier quarrelled with Prince Bohemond IV, who was confiscating church properties to make up shortfalls of cash. Himself short of money, Rainier attempted to reignite Antioch's claim to the archdiocese of Tyre, which responded by claiming jurisdiction over the church in the County of Tripoli, which was under Antiochene control. Honorius quashed both claim and counterclaim as unprofitable when most of the territory in question was not even in Christian hands.