Maio I Orsini

Matthew or Maio Orsini (; died after January 1238) or alternatively Matthew/Maio de Monopoli was a Count palatine of Cephalonia and Zakynthos.

Life Matthew's origin is obscure. Follwing the—mostly conjectured—genealogy presented by the 19th-century scholar Karl Hopf, he has generally been considered in older historiography to be a scion of the noble Roman House of Orsini, the son of a certain Richard Orsini and a daughter of admiral Margaritus of Brindisi, who had conquered the Byzantine islands of Cephalonia, Zakynthos, and Ithaca during the Third Norman invasion of the Balkans in 1185. Other scholars on the other hand have considered him Margaritus' son-in-law. In both cases, it is considered that he succeeded Margaritus in his rule over Cephalonia, Zakynthos, and Ithaca, following the latter's disgrace in 1194. Like Margaritus, Matthew acknowledged the suzerainty of the Norman Kings of Sicily.

More recent research has cast doubt on this traditional account: Matthew was most likely from Monopoli in Apulia, and appears to have been unrelated to Margaritus. Even his supposed surname, Orsini, is not attested in any primary sources, either for himself or any of his descendants, and modern historians have denied it's historicity, viewing it as pure conjecture on Hopf's part. The Aragonese version of the Chronicle of the Morea offers an alternative background, reporting that Maio was a simple (but respected amongst his peers) swine herder who, after a clash with local authorities, had been expelled from Monopoli and fled to Cephalonia with his followers, where he married the daughter of the local Byzantine governor before extending his rule over the neighbouring islands . While previous scholars dismissed this version, it may have been closer to reality according to the historian Andreas Kiesewetter, while it is also partially confirmed by another source, the Breve Chronicon de Rebus Siculis, where Matthew is mentioned as "Apulus, de civitate Monopoli". As historian Brendan Oswald has also pointed out, this ignoble origin for Matthew and his dynasty might also explain the lack of a family name in sources, and their mention simply with their title, as "de Cefalonia".

The last record of Matthew is a letter sent to him by Pope Gregory IX in January 1238, exhorting him to come to the defence of Constantinople against the Greeks of the Empire of Nicaea. Count Richard Orsini is often considered his son and successor, but this is problematic for chronological reasons. It is likely that Matthew was succeeded by another person, possibly named Theodore, who would then be the father of Richard.