The Banu Hilal (Arabic: بنو هلال) were a confederation of Arabian Bedouin tribes that originating from the Hijaz and Nedj and migrated from Upper Egypt into North Africa in the 11th century, having been sent by the Fatimids to punish the Berber dynasty of the Zirids for abandoning Shiism. Other authors suggest that the tribes left the grasslands on the upper Nile because of environmental degradation accompanying the Medieval Warm Period. The Banu Hilal quickly defeated the Zirids and deeply weakened the neighboring Hammadids. Their influx was a major factor in the linguistic, cultural and ethnic Arabization of the Maghreb, and in the spread of nomadism in areas where agriculture had previously been dominant. Ibn Khaldun noted that the lands ravaged by Banu Hilal invaders had become completely arid desert.
They were led by Abu Zayd al-Hilali. Their story is recounted in fictionalized form in Taghribat Bani Hilal.
Their "saga" is still recounted in form of poetry in Algeria, Tunisia and Egypt: Djezia and Dhieb bin Ghanim opposed to the Zenati Khalifa.