The Moroccan expedition crossed the Sahara toward Songhay after Askiya Ishaq rejected the Moroccan sultan’s ultimatum. Songhay messengers appealed to tribal shaykhs along the route to fill the desert water holes, but Tuareg attacked and wounded them before they could obstruct the advancing army. The Moroccan force therefore reached the Niger region after surviving the desert crossing, while the Songhay army was assembled hastily.

Moroccan troops arrived at Karabara near Bamba and advanced toward Gao. Askiya Ishaq brought his army to Tondibi, where the decisive engagement took place. The size of the Songhay force was disputed, with estimates ranging from 10,000 to 18,000 cavalry and from 30,000 to 100,000 infantry. These divergent figures indicate the difficulty of assessing the scale of the battle.

The askiya ordered cattle to move in front of his army, hoping that the herd would disorder the Moroccan ranks. At the first volley, however, the cattle turned back and threw the Songhay formation into confusion; another account says the Moroccans opened their ranks and then closed them behind the herd. Moroccan fire quickly routed most of the Songhay army. Only the rearguard maintained its position, shooting arrows until it was overcome in hand-to-hand combat.

The Moroccans did not pursue the defeated army, which crossed the river toward Gurma. Judar entered Gao, finding the capital almost deserted. The battle caused heavy losses, including civilians who died while crossing the river in panic. Its consequences extended beyond the battlefield: Askiya Ishaq offered submission and tribute, but the Moroccan sultan rejected the terms and continued the conquest of Songhay.