A Mediterranean king.

When Egesarius’s brother, the barbarian king Milocrates, was invaded by Roman warriors, including a young Gawaine, he sent a message to Egesarius asking for help. Egesarius left immediately, but was held up by storms and arrived too late, meeting the victorious Roman fleet as it was leaving the island.

Through the heroics of Gawaine, Egesarius was killed and his ships were sunk by Greek Fire or captured.

Elsewhere in the story, the same character seems to be called Buzafarnan.

De Ortu Waluuanii Nepotis Arturi | Late 13th century