After the abdication of Hasan, Muawiya became an absolute ruler of the Islamic state, which he diplomatically acquired on the ground of Revenge of Uthman's blood, and it must be pointed out that when he became absolute ruler, neither he investigated the assassin of Uthman, nor he did care for this issue. It was mere a pretext to remove Ali from his caliphate. In sum, he succeeded to establish the Umayyad rule in Syria.
Perhaps the most important event in the history of the development of the Shiite passion was Muawiya's nomination of his son Yazid to succeed him. He could not act in this direction as long as Hasan lived, and it is significant that immediately after the news of Hasan's death, Muawiya began actively on the project that would fulfil his long desire of perpetuating the rule of his family. This was however not an easy task, and he had to move with great caution and use all devices: diplomacy, generous gifts, bribes, and finally threat and oppression.
The early Arabic traces of the first century of Islam are rich in information, mostly tinged with legends and miracles. We may safely divide the sources into two groups. The one is the Nasibi sources i.e., official Umayyad reports and sayings of their partisans, circulated chiefly during the reigns of Abdul Malik and Hisham. The second one is supported with the sayings of Umm Salmah, some companions of Muhammad and the traditions transmitted by descendant of Hussain. This version was first recorded by Abu Mikhnaf (d. 157/774), who was the author of about 32 works. Tabari (d. 310/922) provides the fullest account; the narrative of Baladhuri (d. 279/892) and Ibn Atham al-Kufi al-Kindi (d. 314/926) are almost as full. It is worth mentioning that these three historians all utilized the earlier histories of Abu Mikhnaf (d. 157/774), Madaini, Ibn al-Kalbi, Awana bin al-Hakim and Waqidi (d. 207/822). Tabari however relies almost entirely on the narrative of Abu Mikhnaf, whose importance lies in the fact that he uses the accounts of eye-witnesses such as Hamid bin Muslim al-Azdi, al-Shabi and Abdur Rahman bin Abil Kanud. We have therefore derived our informations mostly from the source of Tabari in relating the forthcoming tragedy of Karbala.
Muawiya died in 60/680 after ruling for 19 years and 3 months. With his death, his son Yazid issued orders to his governor of Medina, Walid bin Utba, to exact homage from Hussain and Abdullah bin Zubayr. In his letter to the governor, he gave strict orders that they should not be allowed to delay. Walid bin Utba accordingly summoned them in his palace. Abdullah bin Zubayr did not go and fled to Mecca. Hussain went to the palace alone. Walid read to him Yazid's letter and asked for immediate recognition of the new caliph. Hussain replied uncommittedly that the oath, in order to be valid, must be made in public and that the governor should arrange a public gathering in the mosque where he would also be present. With this reply, Hussain rose to leave the palace. Walid bin Utba paid for his lenient attitude towards Hussain, he was shortly thereafter dismissed from his post of governor of Medina.