Targum do Liczb 22:4

And they said to the elders of the Midianee, for the people had been one and the kingdom one unto that day: Now will this congregation consume all that is about them, as the ox eateth up the grass of the field. And Balak bar Zippor, a Midianite, was the king of Moab at that time; without (a Midianite) being such at another time; for so was the tradition among them, to have kings from this people and from that, by turns.