The Twelvers are the largest branch of Shia Islam. The term “Twelver” refers to the belief in twelve imams, the last being Muhammad al-Mahdi who lives in occultation and will reappear as the promised Mahdi. The Twelvers held that the known line of imams through Musa Al Kazim, the seventh imam, came to an end with the eleventh, Hasan Al Askaro who died in the year 874, leaving no heirs to succeed him. The Twelvers then developed a concept of a hidden twelfth imam, Muhammad, who would eventually appear as the Mahdi, the “guided one”, the messiah chosen by God to restore the true faith of Islam and to establish the reign of justice in the world. Until that day comes, and until the Mahdi descends, the