Judges 3:10-14

And the Spirit of the LORD came upon him, and he judged Israel, and went out to war: and the LORD delivered Chushan-rishathaim king of Mesopotamia into his hand; and his hand prevailed against Chushan-rishathaim.

And the land had rest forty years. And Othniel the son of Kenaz died.

And the children of Israel did evil again in the sight of the LORD: and the LORD strengthened Eglon the king of Moab against Israel, because they had done evil in the sight of the LORD.

And he gathered unto him the children of Ammon and Amalek, and went and smote Israel, and possessed the city of palm trees.

So the children of Israel served Eglon the king of Moab eighteen years.