Mushegh III Mamikonian was an Armenian prince and general in the Sasanian army that fought against the Arabs during the Muslim conquest of Persia. He was killed during the Battle of al-Qadisiyyah in 636.
The family of Mushegh III Mamikonian is disputed. The Armenian historian Sebeos calls him a son of Davit Mamikonian. According to Christian Settipani, Davit was probably the son of Hamazasp, who was the son of Mushegh II Mamikonian.[1] However, Cyril Toumanoff considers Davit to be the son of Vahan II. Historians, however, agree that Mushegh was the elder brother of Hamazasp IV and Grigor I Mamikonian, who were both princes of Armenia.
In 636, Mushegh III, at the head of an army of 3000 men, and Grigor, prince of Syunik, at the head of 1000 men, were the Armenian contingent who joined the army of Rostam Farrokhzad, the spahbed of the Sasanian forces, who was preparing to fight the Muslim Arabs who were camping at Qаdisiyyah. Mushegh, along with his two nephews, died during the battle. Grigor of Syunik, along with his one son, and Rostam and much of the Sasanian army were also killed in the battle.[2] In Parvaneh Pourshariati's view, Mushegh may be identifiable with Jalinus, a Sasanian general mentioned in Arabic sources who also died at Qadisiyyah.
According to Cyril Toumanoff, and some other historians, Mushegh had a son named Mushegh IV Mamikonian, who was also a sparapet and prince of Armenia.