The period in question is the period three caliphs and his abstention from public or political involvement, and his tenure as the fourth of the rightly guided caliphs (from the Sunni point of view). The obstacles that confronted him - you could talk about the existence of a rival centre of power in Damascus under the auspice of Mu’awiyah, who using the assassination of Uthman the third caliph as a pretext now wished to deny legitimacy to Imam Ali [AS] and refused him his loyalty and his obedience.
1After the Prophet [sAW] himself there is no other figure in Islamic History who has exercised the same comprehensive and lasting influence as Imam Ali [AS]. This can in part be seen from the duality of titles that one may be applied to him with respect to Sunni and Shi'ah tradition respectively. From the Sunni point of view he is the fourth among the rightly guided caliphs, from the Shi’ah point of view he is the first of he 12 Imams [AS], that in itself indicates that he holds an honoured position in the totality of Islamic tradition despite varying interpretations.
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