Arwa bint Mansur al-Himyari

Arwā bint Manṣūr al-Ḥimyarī (أروى بنت منصور الحميرى) also known as Umm Mūsā (ام موسى) was the famous principal wife of Abbasid caliph al-Mansur (r. 754–775) and mother of third Abbasid caliph al-Mahdi.

Biography
Arwa was the daughter of Mansur al-Himyari, a descendant of the Banu Himyar tribe, whose ancestors ruled Yemen in pre-Islamic times (110 BCE–525 CE). She was Al-Mansur's first wife. Arwa was also known as Umm Musa, her lineage went back to the Kings of Himyarite.

She married Abu Ja'far Abdallah ibn Muhammad, the future Abbasid caliph al-Mansur. She had two sons from her marriage, Ja'far and Muhammad, who became caliph al-Mahdi. According to their pre-marital agreement, while Arwa was still alive al-Mansur had no right to take other wives and have concubines. Al-Mansur tried to annul this agreement several times, but Arwa always managed to convince the judges not to do that. The two sons of Arwa, Muhammad and Ja'far were regarded as his heirs.

Her first son, Ja'far, was born in 742/743 and her second son, Muhammad, was born in 744 or 745 in the village of Humeima (modern-day Jordan).

When her brother-in-law, al-Saffah, died after a five-year reign, her husband al-Mansur became caliph and held on to power for nearly 22 years, from 754 to 775. Al-Mansur was proclaimed Caliph on his way to Mecca in the year 753 (136 AH) and was inaugurated the following year. Arwa convinced her husband to name only her two sons as heirs.

Her only son Muhammad was old enough to place in succession, Her elder son died during the reign of al-Mansur. Arwa died in 764, at the age of 29. It was only after her death that al-Mansur took other wives.

She had a brother named Yazid. His full name was Yazid ibn Mansur al-Himyari.

Her paternal nephew, Mansur ibn Yazid ibn Mansur al-Himyari held important positions in Caliphate. In 779 he spent two months as governor of Egypt. Between 781/2 and 783 he was governor of the Yemen, and in 796 he briefly served as the governor of Khurasan.