Tetrarch

A ruler over one quarter of a region; a son of Herod the Great who ruled one quarter of the area originally ruled by his father.

Herod Archelaus, governor of Judea, Idumea and Samaria

Matthew 2:22 The tetrarchy system had been started by Philip of Macedon and adopted by the Romans.

But when he learned that Archelaus was reigning in Judea in place of his father Herod, he was afraid to go there. And having been warned in a dream, he withdrew to the district of Galilee,

Herod Antipas, tetrarch of Galilee and Perea

See also Matthew 14:1, Matthew 14:9 Sometimes a tetrarch would be given the courtesy title of king; Mark 6:14 parallel Luke 9:7; Luke 3:1, Luke 3:19, Luke 23:7; Acts 13:1

Herod Philip, tetrarch of Iturea and Traconitis

Luke 3:1

Lysanias, tetrarch of Abilene

Luke 3:1