Ewander
One of the various kings that were said to have ruled Syria during the traditional Arthurian period.
He owed his allegiance to Rome, and he therefore joined Emperor Lucius’s war against Arthur. Evander, with three others, was assigned by Lucius to liberate the Roman prisoners being taken by Arthur’s warriors to a prison in Paris. The Britons won the battle thanks to the timely arrival of Duke Guitard, but Evander killed Earl Borel of Maine.
Evander himself was captured or killed when the Romans began to flee (the Vulgate Merlin says he was killed by Yder). The Alliterative Morte Arthure names Evander and the King of Syria as two separate characters; Evander becomes simply an earl of the Orient.
Sources
Historia Regum Britanniae | Geoffrey of Monmouth, c. 1138
Roman de Brut | Wace, c. 1155
Brut | Layamon, late 12th century to mid-13th century
Vulgate Merlin | 1220-1235
Alliterative Morte Arthure | c. 1400