early 850s) was the emir of Arzen, located on the borders between Upper Mesopotamia (Arabic: al-Jazira) and Armenia, which at the time were provinces of the Abbasid Caliphate.
[5] His ties to the powerful Bagratuni prince certainly strengthened Musa's own position against other rivals, both Christian and Muslim, but it did not stop him from developing a certain enmity towards Bagrat and taking up arms against him.
[5] Thus, when the Abbasid governor, Abu Sa'id Muhammad al-Marwazi, sought to reduce the power and autonomy of the Armenian princes, that had grown greatly during the previous years, he chose Musa and another local Arab lord, al-Ala ibn Ahmad al-Azdi.
Musa invaded Taron, while al-Ala attacked the other great southern Armenian principality of Vaspurakan, ruled by Ashot I Artsruni.
[8] In c. 890 he was taken prisoner by the ambitious Shaybanid ruler of Diyar Bakr, Ahmad ibn Isa al-Shaybani, who annexed the Zurarid domains.