(The emigration from Mecca to Medina marks the date of...

(The emigration from Mecca to Medina marks the date of origin of the Islamic calendar, known as the hijrah.) Ali also served by fighting in the battles of Badr, Uhud, Khaybar, Khandaq, and Hunayn in which the victories achieved with his aid were such that if Ali had not been present the enemy would most likely have uprooted Islam and the Muslims, as is recounted in the usual histories, lives of the Prophet, and collections of hadith.

For Shi'ites, the central evidence of Ali's legitimacy as successor to the Prophet is the event of Ghadir Khumm [5] when the Prophet chose Ali to the "general guardianship" (walayat-i 'ammah) of the people and made Ali, like himself, their "guardian" (wali).

[6] It is obvious that because of such distinctive services and recognition, because of Ali's special virtues which were acclaimed by all, [7] and because of the great love the Prophet showed for him, [8] some of the companions of the Prophet who knew Ali well, and who were champions of virtue and truth, came to love him. They assembled around Ali and followed him to such an extent that many others began to consider their love for him excessive and a few perhaps also became jealous of him.

Besides all these elements, we see in many sayings of the Prophet reference to the "shi'ah of Ali" and the "shi'ah of the Household of the Prophet." [9] The Cause of the Separation of the Shi'ite Minority from the Sunni Majority The friends and followers of Ali believed that after the death of the Prophet the caliphate and religious authority (marja'iyat-i 'ilmi) belonged to Ali.

This belief came from their consideration of Ali's position and station in relation to the Prophet, his relation to the chosen among the companions, as well as his relation to Muslims in general. It was only the events that occurred during the few days of the Prophet's final illness that indicated that there was opposition to their view.

[10] Contrary to their expectation, at the very moment when the Prophet died and his body lay still unburied, while his household and a few companions were occupied with providing for his burial and funeral service, the friends and followers of Ali received news of the activity of another group who had gone to the mosque where the community was gathered faced with this sudden loss of its leader.