Renier of Montferrat

Renier of Montferrat (in Italian, Ranieri di Monferrato) (1162–1183) was the fifth son of William V of Montferrat and Judith of Babenberg. He became son-in-law of the Byzantine Emperor Manuel I Komnenos and Caesar in 1180, and was later murdered in a Byzantine power-struggle.

It was Manuel who suggested the marriage of his daughter Maria the Porphyrogenita to a son of William V. Since Conrad and Boniface were already married, and Frederick was in the priesthood, the only eligible son was the youngest, 17-year-old Renier. The Byzantine chronicler Niketas Choniates described him as handsome, blond (his hair "shone like the sun") and beardless.

Renier arrived in Constantinople in autumn 1179 and soon afterwards accompanied Manuel on a military expedition. His marriage to the 27-year-old Maria took place at the Church of St. Mary of Blachernae, in February 1180. The wedding was celebrated with lavish festivity including games in the Hippodrome of Constantinople, as fully described by the Latin Patriarch of Jerusalem, William of Tyre, who happened to be present. Renier was given the title Caesar, was renamed John, and (according to some Western sources) was granted Thessalonica, presumably as an estate for life, a pronoia. Maria was second in line to the throne, and had only been deprived of the succession by the birth of her much younger half-brother Alexios. Thus Renier became entangled in the perpetual power struggle around the Byzantine throne.

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