Judges 18:29

Dan. They named their new headquarters city after the name of their tribe, which in turn was named after Dan, whom Bilhah, Rachel’s handmaid, bore to Jacob.

Dan’s location in the north is mentioned in the song of Deborah (ch. 5:17). This clearly shows that the migration described in chs. 17 and 18 took place in the earliest part of the judges period. It probably occurred during the days of the elders who followed Joshua, prior to the judgeship of Othniel. This migration and the idolatry described in connection with it were depicted by the author of Judges as illustrative of the apostasy and lawlessness of the period which resulted in the successive invasions and oppressions.