Abbasa was the daughter of the third
Abbasid caliph,
al-Mahdi, and a
concubine of the
Abbasid harem by the name of Rahim, thus she was the mother of his oldest surviving girl child, Abbasa. She was the
half-sister of al-Hadi, Harun al-Rashid,
Ulayya, and
Ibrahim ibn al-Mahdi. She was born during her grandfather reign, her father became caliph in 775. When Abbasa was a young her father arranged her marriage to a cadet member of
Abbasid House. Her husband was
Muhammad ibn Sulayman, a prominent member of a cadet branch of the Abbasid dynasty, who was a long-time governor of
Kufa and
Basra. however her husband died in mid-November 789 and Abbasa became a widow. She married again another Abbasid member during the reign of her brother
Harun al-Rashid. Her second marriage was with
Ibrahim ibn Salih, a member of another cadet branch of the Abbasid dynasty: he was a first cousin to the first two Abbasid caliphs
al-Saffah () and
al-Mansur (). He also became a son-in-law to the third Abbasid caliph
al-Mahdi () by virtue of his marriage to the latter's daughter Abbasa. Ibrahim died in 792, shortly after having been appointed governor of Egypt a second time. After her second husband's death, Abbasa spend rest of her life as a widow in his brother's caliphal palace. She died around
800s. ==Siblings==