It seems that Sayf Ibn ‘Umar was influenced by the nascent Shiite movements in his description of the catastrophic events that took place during the caliphate of ‘Uthmdn and ‘Alt His narrations reveal his strong aversion to the idea that the companions of the Prophet Muhammad might have erred in political issues. However, a careful historical investigation and an objective political analysis of the events of that period reveal the irrationality to seek out such a conspirator as ‘Abdallah Ibn Saba to explain these calamities. The historians such as Tôabarî, Ibn Athîr, and Ibn Kathîr base their descriptions of the events on the reports of Sayf, presenting Ibn Saba as a leading actor. Looking at the same figure with the eyes of heresiographers, however, we get quite a different picture. While they tend to describe Ibn Saba as a dominantly political character who acted around ‘Uthmdn and Alî, the heresiographers incline to picture him as a religious and sectarian personality who masterminded and espoused extreme ideas. These two conflicting tendencies lead one to think that both groups of the scholars portray this mythological figure as they wish