Patriarch John VIII of Constantinople
John VIII Xiphilinos (Greek: Ἰωάννης Ηʹ Ξιφιλῖνος; c. 1010 – 2 August 1075), a native of Trebizond, was a Byzantine intellectual, jurist, and patriarch of Constantinople from 1064 to 1075. He was the uncle of John Xiphilinus, the Epimator. He is considered "an innovator in the field of the methodology of jurisprudential research."