The second Islamic dynasty of Islam, the Abbasids, had the caliphate in 132/750 after the Umayyads' collapse by means of a long-term revolutionary movement. After they took over the power, they shaped their policies under the influence of the revolution. Their primary goal was to defend themselves for their caliphate's legitimate right and impose this on the Islamic society. These efforts had continued for a long time after the first Abbasid Caliph declared himself "the new caliph" in such a way they had been continued during the revolution. The aim for proving the legitimacy of the dynasty was reflected by the works written in this period to a certain extent. Amongst these works, a manuscript known as Akhbar al-Abbas, found in the 1950s in Baghdad, has an important place in the history of the revolution. Although the source has been referenced in many studies, it has not been evaluated in a study in terms of Islamic historiography as a means of the legitimacy of the Abbasid power until now. This article is written to examine the purpose of writing by supposing Akhbar al-Abbas as a manipulative and biased source. The source will be evaluated in light of the new questions to the Islamic historiography and discussions on the Abbasid Revolution in the modern period. The study includes specific chapters from the source, and these chapters will be presented concerning the discussion topics. Thus, a source of Islamic history which is dated to the 3rd/9th century will be discussed as well as the history of the Abbasid Revolution and ideological historiography will be analysed based on da`wa, dawla and legitimacy.