section_path: Descendants of Ali/Under the Abbasids (750 – 1258)
section_name: Under the Abbasids (750 – 1258)
paragraph_text: Under the Abbasids (750 – 1258)
  
  Alids were also persecuted under the Abbasids, who toppled the Umayyads in 750. Some of the Alids thus revolted, while some established regional dynasties in remote areas. In particular, through imprisonment or surveillance, the Abbasids removed the imams of the Imamites from public life, and they are thought to be responsible for the imams' deaths. Mainstream Imamites were the antecedents of the Twelvers, who believe that their twelfth and final imam, Muhammad al-Mahdi, was born around 868, but was hidden from the public in 874 for fear of persecution. He remains in occultation by divine will until his reappearance at the end of time to eradicate injustice and evil. The only historic split among the Imamites happened when their sixth imam, Ja'far al-Sadiq, died in 765. Some claimed that his designated successor was his son Isma'il, who had predeceased al-Sadiq. These were the antecedents of the Isma'ilites, who found political success at the turn of the tenth century, as the Fatimid Caliphate in Egypt and the Qarmatians in Bahrain.