In 909, Abdullah al-Mahdi Billah, a claimant to the Ismaili Imamate, established the Fatimid Caliphate. During this period, three lineages of imams formed. The first branch, known today as the Druze, began with Al-Hakim bi-Amr Allah. Born in 386 AH (985), he ascended as ruler at the age of eleven. The typical religiously tolerant Fatimid Empire saw much persecution under his reign. When in 411 AH (1021) his mule returned without him, soaked in blood, a religious group that was forming in his lifetime broke off from mainstream Ismailism and did not acknowledge his successor. Later to be known as the Druze, they believe al-Hakim to be the incarnation of God and the prophesied Mahdi who would one day return and bring justice to the world. The faith further split from Ismailism as it developed very unusual doctrines which often class it separately from both Ismailiyyah and Islam, and today most Druze do not identify themselves as Muslims.