The Lord instructed Moses to lead Israel in a war against the Midianites. The Midianites had joined the Moabites in influencing the Hebrews to worship idols (chapter 25). The Midianites were a tribal people living in the dry regions south and east of Palestine and east of the Jordan River. They were among the "people of the east" (Judges 6:3, 33; 7:12). They lived in camps or settlements and were famous for their desert transportation skills (compare Genesis 37:28, 36; Isaiah 60:6).
They descended from Abraham and had been friendly to Moses (Genesis 25:1–2; Exodus 2:15–3:1; compare Numbers 10:29). Yet, the elders of Midian joined Balak in hiring Balaam to curse Israel (22:4, 7). Israel's presence threatened the peoples of Transjordan (the area east of the Jordan River).