The Battle of Toulouse (721) was a victory of an Aquitanian Christian army led by Duke Odo of Aquitaine over an Umayyad Muslim army besieging the city of Toulouse, and led by the governor of Al-Andalus, Al-Samh ibn Malik al-Khawlani. The victory checked the spread of Umayyad control westward from Narbonne into Aquitaine.

Odo the Great (also called Eudes or Eudo) (died 735–740), was the Duke of Aquitaine by 700. His territory included Vasconia in the south-west of Gaul and the Duchy of Aquitaine (at that point located north-east of the river Garonne), a realm extending from the Loire to the Pyrenees, with the capital in Toulouse. He fought the Carolingian Franks and made alliances with the Moors to combat them. He retained this domain until 735. He is remembered for defeating the Umayyads in 721 in the Battle of Toulouse. He was the first to defeat them decisively in Western Europe. The feat earned him the epithet "the Great". He also played a crucial role in the Battle of Tours, working closely with Charles Martel, whose alliance he sought after the Umayyad invasion of what is now southern France in 732.