The abnÃÂþ ad-dawla (, meaning "sons of the regime/dynasty"), often " the AbnÃÂþ", refers to the Khorasani Arabs who participated in the Abbasid Revolution of 749âÂÂ750 and their descendants who settled in Baghdad and Iraq. They became the ruling elite of the Abbasid Caliphate and formed the mainstay of the caliphal army. The term rarely appears in the sources until the Fourth Fitna civil war in the 810s, when it was applied to the Khurasanis of Baghdad, who overwhelmingly supported Caliph al-Amin against his brother al-Ma'mun. The terms ahl KhurÃÂsÃÂn ("people of Khurasan") and abnÃÂþ ahl KhurÃÂsÃÂn ("sons of the people of Khurasan") are more frequently used for the Khurasanis who formed the mainstay of the Abbasid regime in general. Following al-Ma'mun's victory in the civil war, the abnÃÂþ al-dawla were largely replaced by the latter's Persian followers, and under his successor al-Mu'tasim, the rise of the Turkish slave-soldiers to power began.