“beyond the River.” The “River” is the Euphrates. The governor of the Persian province on the other side of the Euphrates, hundreds of miles away, had a residence in Jerusalem. It was very common for powerful people in an empire as large as Persia to have palaces in many major cities, and for kings to have palaces in many cities of their realm. King Herod, for example, had palaces in Jerusalem, Caesarea, and Jericho, as well as outside Bethlehem (the Herodian) and in the Judean Wilderness (Masada).