Muhammad ibn Ali ibn Abdallah

Muḥammad ibn ʿAlī ibn ʿAbd Allāh (محمد بن علي بن عبد الله) or Muḥammad al-Imām (679/80 - 743) was the son of Ali ibn Abd Allah ibn al-Abbas and great-grandson of al-‘Abbas ibn ‘Abd al-Muttalib, the uncle of the Islamic prophet, Muhammad. He was the father of the two first 'Abbâsid caliphs, Al-Saffah and Al-Mansur, and as such was the progenitor of the Abbasid dynasty.

Revolt of Mukhtar al-Thaqafi
When al-Mukhtar announced the revenge of Imam al-Husayn, he showed himself as the representative of Muhammad ibn al-Hanafiyyah, the Promised Mehdi according to him.

Imam of the Hashimiyya
After the death of Muhammad ibn al-Hanafiyyah, the imamate of the Kaysanite Shia transferred to his son Abu Hashim, who transferred it to Muhammad, paving the way for the Abbasid dawa and the Abbasid Revolution.