Umayyad tradition of cursing Ali

During the Umayyad Caliphate, cursing Ali ibn Abi Talib, the cousin and son-in-law of the Islamic prophet Muhammad, who was also the fourth Rashidun caliph ((r. 656 – 661)) and the first Shia Imam, was a state policy reportedly introduced by Mu'awiya ibn Abi Sufyan, the first Umayyad caliph ((r. 661 – 680)). Mu'awiya was the incumbent governor of Syria who had rebelled against Ali ostensibly to avenge the previous caliph Uthman ((r. 644 – 656)), who was in turn assassinated by some provincial dissidents angered by his policies. Ali and Mu'awiya fought the inconclusive Battle of Siffin in 657 CE and remained enemies until the assassination of Ali in 661, which paved the way for the caliphate of Mu'awiya in the same year. The public cursing of Ali continued after Mu'awiya and was finally abandoned some sixty years later by the pious Umar ibn Abd al-Aziz ((r. 717 – 720)). The policy likely served as a propaganda measure, and also helped provoke, identify, and then crush the supporters of Ali, whom the Umayyads considered a threat. The historicity of such a policy is supported by Shia Muslims whereas it has remained disputed amongst Sunni Muslim scholars.

Background
The controversial policies of the third caliph Uthman resulted in a rebellion that led to his assassination in 656 CE. Ali ibn Abi Talib, the cousin and son-in-law of the Islamic prophet Muhammad, was subsequently elected caliph by the Medinans and the dissidents. There Ali received a nearly unanimous pledge of allegiance, gathering various underprivileged groups around himself. By contrast, Ali found limited support among the powerful Quraysh tribe, some of whom aspired to the title of caliph. Among the Quraysh, the caliphate of Ali was soon challenged by Aisha, a widow of Muhammad, and two of his companions, namely, Talha and Zubayr. Uthman's distant cousin Mu'awiya also denounced the accession of Ali when he was dismissed from his post as the governor of Syria. He now demanded retribution against Uthman's killers.

Ali defeated the rebellion of Aisha, Talha, and Zubayr in the Battle of the Camel in 656, but the Battle of Siffin against Mu'awiya in 657 resulted in a stalemate when the latter called for arbitration by the Quran to avoid defeat. The strong peace sentiments in Ali's army compelled him to accept the offer, and an ill-fated arbitration committee was thus set up with representatives from Ali and Mu'awiya with a mandate to settle the dispute in the spirit of the Quran. Soon after the collapse of the arbitration process, Mu'awiya received the Syrians' pledge as caliph in 659, and began dispatching military units to raid and harass the civilian population loyal to Ali. In the meantime, a group that became known as the Kharijites deserted Ali, denounced him for agreeing to arbitration, and declared him, his followers, and the Syrians as infidels. They considered the blood of such infidels to be licit, and committed many murders. Ali crushed them in the Battle of Nahrawan in 658, but was later assassinated by the Kharijite Ibn Muljam in 661. This paved the way for Mu'awiya, who founded the Umayyad Caliphate in the same year.

The practice
After his accession, Mu'awiya mandated cursing Ali as part of the communal prayers in the Islamic territories. Among others, this is reported by the Shia-leaning historians al-Ya'qubi and al-Mas'udi  and the Sunni historians al-Tabari  and Abulfeda. In particular, Mu'awiya ordered his governor of Kufa, al-Mughira, to regularly curse Ali and harass his followers, while praising Uthman and empowering his followers, as reported by al-Tabari. A tradition attributed to al-Mughira's son describes how the governor failed to convince Mu'awiya to abandon this policy and leave behind a legacy of reconciliation. Mua'wiya refused, saying that there would be no lasting fame after Muhammad, referring to the prophet by his nickname of Ibn Abi Kabsha among the Meccan infidels. The governor then confessed to his son that he henceforth considered Mu'awiya as such, an infidel, as reported by the Sunni historian al-Zubayr ibn Bakkar. While probably not authentic, the account may nevertheless reflect the attitude towards Mu'awiya among early Sunni historians.

The practice of cursing Ali continued for some sixty years, and the Umayyad caliphs did so also on the Day of Arafa during the annual Hajj pilgrimage. The curse was also apparently extended to Ali's wife Fatima and their sons Hasan and Husayn. These were the daughter of Muhammad and his grandsons, respectively. The practice came to an end under the Umayyad caliph Umar II ((r. 717 – 720)), often known for his piety, who reportedly replaced the curse with verses 59:15 and 16:90 from the Quran. Caliph Hisham ((r. 724 – 743)) followed suit later and did not vilify Ali on Arafa, apparently ignoring protests by Abd-Allah ibn al-Walid, the grandson of Uthman.

That this practice was widespread is also the Shia view, while its existence is usually rejected by Sunni scholars, perhaps with the notable exception of Abul A'la Maududi, the founder of the Islamic movement Jamaat-e-Islami. Maududi believes that not even al-Masjid al-Nabawi in Medina was exempted from this policy, where Ali and other relatives of Muhammad were cursed next to his grave and in the presence of the descendants of Ali. The historian Husain M. Jafri considers this practice a propaganda measure, while the Islamicist Wilferd Madelung suggests that the rule of Mu'awiya was largely legitimized by his revenge for the assassination of Uthman, for which Mu'awiya publicly blamed Ali after the latter dismissed the former as the governor of Syria. In a tradition cited by the Sunni historians al-Baladhuri and Ibn Asakir, the Umayyad Marwan explains to the apolitical Ali al-Sajjad that his grandfather Ali ibn Abi Talib was the most temperate (akaff) among early Muslims to Uthman. According to this report, Marwan then added that Ali was nevertheless cursed because the Umayyad rule would not be sound otherwise. The practice was also perhaps intended to provoke, identify, and then crush the supporters of Ali. Among its first victims was Hujr ibn Adi. Indeed, Ali considered it excusable for his supporters to curse him (under duress) but apparently had not allowed them to dissociate (bara'ah) themselves from him, according to the Islamicist Maria M. Dakake.

Hujr ibn Adi
Hujr was a companion of Muhammad and an ardent supporter of Ali. Respected for his piety, Hujr was in Kufa a distinguished elder of his tribe, the Kinda, though not its leader. After the accession of Mu'awiya, he regularly protested the cursing of Ali in the mosque, which was tolerated by al-Mughira but not by his successor Ziyad ibn Abihi, who was appointed in 671 to govern Kufa. Ziyad arrested Hujr and sent him to Mu'awiya, who put Hujr on trial for high treason and then executed him and a few others. Before death, he was given the opportunity to save his life by cursing Ali, which he refused. This was probably the first judicial execution of Muslims for high treason and was widely condemned at the time, even by Aisha bint Abi Bakr, who was otherwise hostile to Ali. Later the execution of Hujr was called a pernicious crime by the Sunni theologian Hasan al-Basri. Nevertheless, early historians are at odds about Hujr. The early (Sunni) traditionist Hisham is hostile to Hujr while the Shia-leaning historians Abu Mikhnaf and al-Mas'udi are sympathetic to him. Among modern authors, the execution is condemned by Madelung and by the Muslim author Tarek Fatah, while Wellhausen sides with Mu'awiya.

Other cases
Under the Umayyads, some Shias were forced to curse Ali to save their lives. One instance is the hadith traditionist Atiya ibn Sa'd Awfi, who fled to Sind when the revolt by al-Ash'ath was crushed by the Umayyad governor al-Hajjaj circa 701. There Atiya was captured by the Umayyad commander Muhammad ibn al-Qasim by order of al-Hajjaj, who also demanded that Atiya curse Ali. He refused and was beaten but likely survived.