Judea came under Roman influence in 63 BCE, when Roman general Pompey arrived in the Levant as part of the Roman campaign against Mithridates VI of Pontus. In 37 BC Rome installed Herod the Great as a client king of Judea, helping him oust the Parthian-backed leader Antigonus II Mattathias. Shortly after Herod's death, Judea was partitioned among his sons as tetrarchy, but due to disturbances by 6 CE it came under direct Roman control and, with the exception of a small autonomous region in the north, became a Roman province, ruled by prefects appointed by Rome.