Final letter of Muhammad al-Mahdi to al-Samarri

The final letter of Muhammad al-Mahdi, known as the Hidden Imam in Twelver Shi'ism, to his agent, Abu al-Hasan Ali ibn Muhammad al-Samarri, predicted the latter's imminent death and announced the beginning of the Major Occultation (941–present). In Twelver belief, the Major Occultation concludes with the rise of al-Mahdi in the end of time to establish peace and justice on earth.