The Banu Qasi, Banu Kasi, Beni Casi, Banu Musa, or al-Qasawi were a Muladí dynasty that in the 9th century ruled the Upper March, a frontier territory of the Umayyad Emirate of Córdoba, located on the upper Ebro Valley. At their height in the 850s, family head Musa ibn Musa al-Qasawi was so powerful and autonomous that he would be called 'The Third Monarch of Hispania'. In the first half of the 10th century, an intra-family succession squabble, rebellions and rivalries with competing families, in the face of vigorous monarchs to the north and south, led to the sequential loss of all of their land.

Muladí were the native population of the Iberian Peninsula who adopted Islam after the Muslim conquest of the Iberian Peninsula in the early 8th century. The demarcation of muladíes from the population of Arab and Berber extraction was relevant in the first centuries of Islamic rule, however, by the 10th century, they diluted into the bulk of the society of al-Andalus. In Sicily, Muslims of local descent or of mixed Arab, and Sicilian origin were also sometimes referred to as Muwallad. They were also called Musalimah ('Islamized'). In broader usage, the word muwallad is used to describe Arabs of mixed parentage, especially those not living in their ancestral homelands.