Beyond the River
was the name given to the Persian province located west of the Euphrates River. This (very large) province had multiple governors (note the plural in Nehemiah 2:9). One of them, the ruler of (the district of) Mizpah
(Nehemiah 3:15, Nehemiah 3:19), had his seat of authority in the town of Mizpah and so presumably lived there. The fact that Mizpah
is described as the seat
adds significance to the willingness of its citizens to assist in rebuilding Jerusalem’s walls.
7 And next to them repaired Melatiah the Gibeonite and Jadon the Meronothite, the men of Gibeon and of Mizpah, the seat of the governor of the province Beyond the River.