The children of Israel did that which was evil in the sight of Yahweh: and Yahweh delivered them into the hand of Midian seven years.
The Midianites had been thoroughly defeated by the Israelites under Moses  (Numbers 31), but at this time, "After an interval of 200 years, they had recovered their strength, and God used them as a rod of chastisement for His rebellious people."[5]