Coptic and Arabic inscriptions in an Old Cairo church.
Bashmurian revolt (Arabic ثورة البشموريين) (also Peshmurian revolt) was the revolt of the Coptic Christians living in the Al-Bashmur area in North Nile Delta against the Abbasids, which occurred around 832. The revolt (and others previous) were attributed to "oppressive taxation".
The rebels expelled the state workers and raised the banner of rebellion refusing to pay tribute (special tax on non-Muslims called the jizya). Caliph Al-Ma'mun, who was visiting the province, put down the rebellion, arresting and killing large numbers of Copts and their dependants. According to historian Ira M. Lapidus, the crushing of the rebellion was followed by "despair" among the Copts and mass conversions to Islam, which rendered the ex-Copts exempt from Jizyah tax.
^Goddard, Hugh (2000). A History of Christian-Muslim Relations. Rowman & Littlefield. p. 71. ISBN1566633400. Retrieved 20 January 2016. Large-scale conversion to Islam in Egypt began during the eighth/second century and was very much linked with economic hardship. Oppressive taxation led to a whole series of revolts in different regions of Egypt between 725/107 and 832/217, and these were crushed by the local governors and in the end, the caliph al-Ma'mun himself who visited the province in 832/217.