A son of Bartholomew I Ghisi, through his first marriage to a daughter of Guy II of Dramelay he was Baron of Chalandritsa in the Principality of Achaea.
[1] In that year, following a series of destructive raids in the Greek and Latin-held islands of the Aegean Sea, the Aragonese admiral Roger of Lauria led his fleet to anchor at Navarino.
Fearful lest the Aragonese seize possession of lands in Achaea, or repeat their plundering raids, and with Prince Florent of Hainaut absent in Italy, George assembled two hundred knights at Androusa and attacked the Aragonese.
In a brief but bloody combat, the Achaeans were defeated and George captured, only to be ransomed for 8,000 hyperpyra shortly after when the Aragonese fleet sailed to Glarentsa.
[2][3] In 1303, when his father died, he inherited the lordship of the Aegean islands of Tinos, Mykonos, with fiefs on Serifos and Keos.