to Mu'awiya that he had given up his claim to the caliphate for the sake of peace and compromise, not to fight on his side. Madelung suggests that the relations between the two men deteriorated when Mu'awiya realized that Hasan would not actively support his regime. After his abdication, Hasan retired from politics in Medina. In compliance with the peace treaty, he also declined requests from Shia groups to lead them against Mu'awiya. The Sunni al-Baladhuri () in his Ansab writes that Hasan sent tax collectors to the Fasa and Darabjird provinces of Iran in accordance with the peace treaty but the governor of Basra, instructed by Mu'awiya, incited the people against Hasan and his tax collectors were driven out of the two provinces. Madelung regards this account as fictitious, adding that Hasan had just refused to join Mu'awiya in fighting the Kharijites. He holds that Hasan had made no financial stipulations in his peace proposal and Mu'awiya consequently made no payments to him. Hasan died in 50/670, and the early sources are nearly unanimous that he was poisoned. Mu'awiya is commonly viewed as the instigator in the murder of Hasan, which removed an obstacle to the succession of his son Yazid (), whose nomination violated the treaty with Hasan. Throughout his reign, Mu'awiya also prosecuted notable partisans of Ali, including Hujr ibn Adi, a companion of Muhammad, who was executed in 670. Mu'awiya also institutionalized the regular public cursing of Ali in the congregational prayers. See also Hasan ibn Ali Muawiya I Footnotes References Citations Sources Peace treaties 7th-century treaties First Fitna 7th century in the Umayyad Caliphate 661