For seven years, before the calling of Gideon, God allowed the Midianites (and their allies) to ravage ancient Israel. The Eternal allowed this to happen in order to punish the people for their sins, chief of which was idolatry (Judges 6:1, 8 - 10). The Midianite-led army would regularly enter Israel's territory east of the Jordan River and would sweep both west and south. Their marauding journey would take them as far south as the Philistine-held city of Gaza (verse 4). As the hoard traveled they pillaged and destroyed crops, took whatever cattle and other goods they desired, and even committed mass murder (e.g. against Gideon's family, see Judges 8:18 - 19).
This great army of eastern nomads relied heavily on camels (Judges 6:5), an animal who not only could carry heavy loads and go without water for long periods, but was also relatively fast and could travel up to 100 miles (60 kilometers) in a single day! The destruction and violence caused by the Midianites brought widespread poverty and led the people, including Gideon, to live in constant fear (6:2, 6, 11).
The children of Israel's cries for relief from their suffering are ultimately heard and answered by God. After sending a prophet to remind them of their disobedience (Judges 6:8 - 10), he sends an angel to a man named Gideon. He dwells in the village of Ophrah with his family who are part of the tribe of Manasseh (verses 11, 15). He is commissioned to free the Israelites from their hated enemies (verses 12 - 16).
Soon after Gideon's calling, a vast 135,000-man army gathers in the valley of Jezreel (Judges 6:33, 8:10) near where he lives. They camp in a place close to the hill of Moreh (7:1). Among those in the camp are two Midianite princes named Oreb and Zeeb (Judges 7:25) and two Midian kings named Zebah and Zalmunna (8:5).
Gideon calls for volunteers to fight against the Midianites. An army of 32,000 men arrives in Ophrah from the tribes of Manasseh, Asher, Zebulun and Naphtali (6:34 - 35, 7:3). Once together, they travel to the well of Harod and pitch their camp. The well is positioned just south of the Midianite forces and is located on ground that overlooks the vast enemy below them (7:1, 8 - 9). God, after the camp is pitched, decides to reduce the number of men who will fight to only 300 (7:2 - 7).
The army is divided into three companies that surround the enemy camp. Each of the men carries a trumpet and an easily breakable earthenware pitcher with a lighted torch in it (Judges 7:16). At 10 p.m., when the enemies' second watch of the night begins, Gideon signals the men to blow their trumpets and break their pitchers. They then shout a battle cry (verses 17 - 20). Startled, enemy troops begin killing EACH OTHER and fleeing the area (21 - 22)! Those who flee the valley are pursued by Israelites (7:23).
The Midianites race east toward Beth-shittah and the Jordan River (Judges 7:22). They then travel south, along the river, toward Abel-meholah. Continuing south, the army splits into two groups north of Beth-barah. The first group, led by Oreb and Zeeb, race further down the Jordan toward the city in hopes of fording the river at that point. The second group, led by kings Zebah and Zalmunna, decide to cross the Jordan River north of the city.
Gideon, aware that some of the Midianites might try to cross the river near Beth-barah, sends advance messengers to the tribe of Ephraim asking them to protect several of Jordan's crossings (Judges 7:24). The Ephraimites secure the crossings then battle the approaching enemy. They catch and kill Oreb and Zeeb, cut off their heads, then pursue the remaining men eastward across the Jordan. The heads of the two princes are eventually presented to Gideon (Judges 7:24 - 25).
Gideon and his 300 men, who have chased the Midianites down the Jordan, cross the river in pursuit of the remaining 15,000 enemy fighters led by Zebah and Zalmunna (Judges 8:4, 10). On the eastern side of the Jordan, tired and in need of food for him and his men, he asks the cities of Succoth and Penuel for assistance. The elders of both cities refuse his request for aid (8:5 - 9). They are punished, after the war ends, for their refusal to help their brethren in need (14 - 17).
Midianite forces race toward their land by traveling east, roughly along the Jabbok River, then turning south toward Karkor (Judges 8:10). In Karkor, the 300-man force surprises the enemy by attacking from the east (verse 11). They crush most of the remaining Midian army, pursue the rest, and capture Zebah and Zalmunna (11 - 12). It is discovered, after the cities of Penuel and Succoth are punished, that the two kings massacred members of Gideon's family. They are executed for their actions (verses 18 - 21).