After the episode of the negotiations with the Ammonite king, the story of Jephthah’s actions resumes with his campaign against the Ammonites. It possibly suggests his raising of an army (in which the neighbouring Ephraimites, on the other side of the Jordan, are not included, Judges 12:1–3). The passage does not clarify whether Jephthah was in Mizpah once or twice.
29 Then the Spirit of the LORD was upon Jephthah, and he passed through Gilead and Manasseh and passed on to Mizpah of Gilead, and from Mizpah of Gilead he passed on to the Ammonites.