X. The Tenth Imam, 'Ali, known as al-Naqi (212/827-254/868)
The son of the ninth Imam, he remained in Medina teaching the religious sciences until 243/857, when he was summoned to Samarra by the caliph al-Mutawakkil. There he was treated harshly by the caliph and his successors until he died. He is buried in Samarra.