God's Fifth Lesson - The Rise of the Ammonites and Its Consequences - Jephthah as Judge of Israel (Judges 10:6 to Judges 12:7).
The Sins of Israel and the Oppression of Ammon (Judges 10:6-16).
‘ And the children of Israel did evil again in the sight of the Lord, and served the Baalim, and the Ashtaroth, and the gods of Aram (Syria), and the gods of Zidon, and the gods of Moab, and the gods of the children of Ammon, and the gods of the Philistines, and forsook Yahweh and did not serve him.'
These gods would include Ashtoreth (of Zidon - 1 Kings 11:5; 1 Kings 11:33), Baal-peor and Chemosh (of Moab - Numbers 21:29; Num 25:3; 1 Kings 11:7; 1 Kings 11:33), Melek (Molech, Milcom - of Ammon - Leviticus 18:21; 1Ki 11:5; 1 Kings 11:7; 1 Kings 11:33), and Dagon and Baalzebub (of the Philistines - Judges 16:23; 1 Samuel 5:2-7; 2 Kings 1:2-3). Molech was particularly known as a god requiring human sacrifice (Leviticus 18:21; Leviticus 20:2-5; 2 Kings 23:10; Jeremiah 32:35).
From this it is apparent that a large part of the people were now seeking different gods in different parts of the country. This was to ‘forsake' Yahweh. They no doubt kept up some formal observance of His requirements but they found the other gods more exciting and stimulating, and less demanding, and they could see them and be awed. It may also be that in some cases, such as the Philistines, Ammon and Moab, they were required to worship these gods because of the pressure from their oppressors.
Note that the number of gods mentioned is seven. This was in order to incorporate into the idea all the gods of all the nations, for seven is the number of divine completeness.