Jacopo Gattilusio

Jacopo Gattilusio (or "Giacomo"; died 1428) was the third Lord of Lesbos. He was the eldest son of Francesco II of Lesbos, whom he succeeded as lord of the island on 26 October 1404.
William Miller summarized Jacopo's motivation as a semi-autonomous ruler was to favor Genoese interests when they conflicted with Venetian ones, but to cooperate with both when they showed signs of uniting against his neighbors, the Ottomans. For example, he aided Centurione II Zaccaria, Prince of Achaea against the Tocchi of Cephalonia and Zante.
He had no sons, so on his death he was succeeded by his younger brother Dorino I Gattilusio.
Marriage.
Jacopo was married to Bona Grimaldi. Only one child is known: 
Niccolò mentioned Jacopo as his father-in-law in his correspondence from the year 1426. However the name of his wife remains unknown. Niccolò had eleven children but no record exists of their mother or mothers.
An account by Caterino Zeno dated to 1474 names Niccolò as married to Valenza Megali Komnene, a supposed sister of daughter of John IV of Trebizond. Whether this means Niccolò took a second wife or whether Zeno was in error has been debated by genealogists.