Upper March

The Upper March (in Arabic : الثغر الأعلى , aṯ-Tagr al-A'la; in Spanish: Marca Superior) was an administrative and military division in northeast Al-Andalus, roughly corresponding to the Ebro valley and adjacent Mediterranean coast, from the 8th century to the early 11th century. It was established as a frontier province, or march, of the Emirate, later Caliphate of Córdoba, facing the Christian lands of the Carolingian Empire's Marca Hispanica, the Asturo-Leonese marches of Castile and Alava, and the nascent autonomous Pyrenean principalities. In 1018, the decline of the central Cordoban state allowed the lords of the Upper March to establish in its place the Taifa of Zaragoza.

Following the Muslim conquest of the majority of the Iberian peninsula, the lands of what would become the Upper March were granted to Arab and Berber troops that had participated in the invasion, but unlike other regions, the Ebro valley saw a large number of native families being allowed to keep their lands in exchange for the their conversion to Islam and oaths of fealty. When a Berber Revolt in the early 740s destabilized the frontier, the neighboring Christian Kingdom of Asturias moved into the depopulated lands bordering the Upper March to the west, while Pepin the Strong moved from the north into Septimania in the 750s, establishing the extent of the Upper March. In response to these challenges, an Arab leader in the Ebro valley, Hubab al Zuhri, joined in a 754 rebellion against the leadership in Córdoba, and offered refuge to the exiled Umayyad prince, Abd al-Rahman I, who ended up conquering Al-Andalus to establish the Emirate of Córdoba in 756. He formally established three marches on his frontiers, with the Lower March (aṯ-Ṯaḡr al-Adna) in the northwest, the Middle March (aṯ-Ṯaḡr al-Awsaṭ) in the center-north, and the Upper March, administered out of Zaragoza, in the northeast.

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