Herod Philip was the son of Herod the Great and tetrarch over the northeastern regions of Palestine, including Iturea and Trachonitis. He was known as the most moderate and just of Herod's sons, and founded the city of Caesarea Philippi where Peter confessed Jesus as the Messiah.
Philip is mentioned as tetrarch over Iturea and Trachonitis when John the Baptist began his ministry, providing a historical timeframe for the events of the gospel.
1In the fifteenth year of the reign of Tiberius Caesar, when Pontius Pilate was governor of Judea, Herod tetrarch of Galilee, his brother Philip tetrarch of the region of Ituraea and Trachonitis, and Lysanias tetrarch of Abilene,
In the area around Caesarea Philippi, the city that Philip founded and named after himself and Emperor Augustus, Jesus asked his disciples who people said he was, and Peter confessed him as the Messiah.