In 57–55 BCE, Aulus Gabinius, proconsul of Syria, split the former Hasmonean Kingdom into Galilee, Samaria, and Judea, with five districts of legal and religious councils known as sanhedrin (Greek: συνέδριον, "synedrion"): "And when he had ordained five councils (συνέδρια), he distributed the nation into the same number of parts. So these councils governed the people; the first was at Jerusalem, the second at Gadara, the third at Amathus, the fourth at Jericho, and the fifth at Sepphoris in Galilee.""Josephus uses συνέδριον for the first time in connection with the decree of the Roman governor of Syria, Gabinius (57 BCE), who abolished the constitution and the then existing form of government of Palestine and divided the country into five provinces, at the head of each of which a sanhedrin was placed ("Ant." xiv 5, § 4)." via Jewish Encyclopedia: Sanhedrin
