John Petraliphas

John Petraliphas (Greek: Ἰωάννης Πετραλίφας) was a Byzantine noble and governor of Thessaly and Macedonia in the late 12th/early 13th century with the rank of sebastokrator.

John was a member of the Petraliphas family, which was of Italo-Norman origin. According to the hagiography of his daughter, Theodora of Arta, John was married to a woman called Helena, from an unspecified noble house of Constantinople, and after being raised to the very high rank of sebastokrator, was dispatched by Byzantine emperor Isaac II Angelos (r. 1185–1195 and 1203–1204) to govern Thessaly and Macedonia. Nevertheless, in 1195, he was among the leading nobles who conspired and overthrew Isaac II and installed Alexios III Angelos (r. 1195–1203) in his place.

After 1204, when Constantinople fell to the Fourth Crusade, he supported the ruler of Epirus Theodore Komnenos Doukas, to whom his sister Maria was married. He died probably sometime between 1224 and 1230. Some authors (Donald Nicol and D. Polemis) have equated him with another John Petraliphas, who was a megas chartoularios in the employ of the Empire of Nicaea circa 1237, but this identification is most likely false.

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