ʿAlī b. Abī Ṭālib (Arabic: علي بن أبي طالب) known as Imam ʿAlī (a) (b. 23 BH/600 - d. 40/661) is the first Imam of all the branches of the Shi'a, a companion, a narrator, and a scribe of the Qur'an. He is the fourth caliph of the Rightly Guided Caliphs in Sunni Islam. 'Ali (a) is the cousin, and son-in-law of the Prophet (s), the husband of Lady Fatima (a), and the father of the rest of the Imams of the Shi'a. According to Shi'i historians and many Sunni scholars, he was born inside the Ka'ba. He was also the first convert.
Based on evidence from the Qur'an, hadith, and history, the Shi'a believe that 'Ali (a) was the direct designated successor of the Prophet (s). Some verses of the Qur'an point to his infallibility. According to Shiite and some Sunni sources, roughly three-hundred verses of the Qur'an were revealed with regards to his virtues. When the Quraysh plotted to assassinate the Prophet (s), it was 'Ali (a) who slept where the Prophet (s) used to sleep, and thus helped the Prophet (s) to secretly leave for Medina. In the pact of brotherhood in Medina, the Prophet (s) chose 'Ali (a) as his brother. Except for the Battle of Tabuk when he stayed in Medina as the deputy of the Prophet (s), 'Ali (a) was with the Prophet (s) in all the battles. He was the most proud commander of Islam.
After the Prophet's (s) demise, a group of people pledged allegiance with Abu Bakr in Saqifa as the caliph contrary to what the Prophet had explicitly stipulated in Ghadir. 25 years later after the caliphate of Abu Bakr, 'Umar and 'Uthman, 'Ali (a) accepted the caliphate at the overwhelming insistence of the Muslims. During his short rule, he was faced with three rebellions and was ultimately assassinated by one of the Kharijites while praying in the Mihrab (the prayer niche) of the Kufa Mosque, and was then secretly buried in Najaf.
Ali (a) is considered as the father of many Islamic sciences including Arabic literature, Islamic theology, jurisprudence, and exegesis. Scholars of different sciences have tried to trace back the chain of their hadiths to him. Nahj al-balagha is a selection of his speeches and letters.
Ali b. Abi Talib (a) has always had a high status in the eyes of the Shia. He was the most pious and the most knowledgeable companion of the Prophet (s) and his rightful successor. Because of his virtues, a number of the Companions loved and were attached to Ali (a) at the Prophet's (s) time and were called "Shi'at Ali" (the partisans of Ali) since then. However, the word "Shi'a" came to indicate those who consider Ali (a) the rightful successor of the Prophet (s), in contrast to "Sunnis" who maintain that the rightful successor of the Prophet (s) was chosen by the people.
In the Shiite view, the coming to power of Imam Ali (a) as the caliph on Dhu l-Hijja 19, 35/June 18, 656, was the late execution of the Prophet's (s) multiple instructions in different occasions, especially in Ghadir Khumm, that Ali (a) should succeed him and lead the Muslim community after him. The Shia maintain that the Prophet (s) appointed Ali (a) as his successor by the statement "For whomever I am the master, Ali will be his master." This is what the audience understood at the time and thus congratulated Ali (a) for this appointment, calling him Amir al-Mu'minin (the Commander of the Faithful).
His lineage is Ali b. Abi Talib b. 'Abd al-Muttalib b. Hashim b. Qusayy b. Kilab. He was from Banu Hashim branch of Quraish. Ali's (a) father, Abu Talib was a generous and just man who was respected by various Arab tribes. He was the uncle and guardian of the Prophet (s) and was amongst the most noble personalities of the Quraysh. Ali's (a) mother was Fatima bt. Asad. His brothers were Talib, 'Aqil, and Ja'far and his sisters were Hind (or Umm Hani), Jumana, Rayta (or Umm Talib) and Asma'. According to the historians, the marriage of Abu Talib and Fatima b. Asad was the first marriage between two individuals who were both from the Banu Hashim clan. Thus, Ali (a) was the first person who was a Hashimite from both his father's and his mother's sides.
|[Expand]Family tree of Ahl al-Bayt (a)|
In different sources, variety of titles and attributes are mentioned for him, such as: Amir al-Mu'minin (the Commander of the Faithful), Ya'sub al-Din wa l-Muslimin, Haydar, al-Murtada, Qasim al-Nar wa l-Janna, Sahib al-Liwa', al-Siddiq al-Akbar, al-Faruq, Mubir al-Shirk wa l-Mushrikin, Qatil al-Nakithin wa al-Qasitin wa al-Mariqin, Mawla al-Mu'minin, Shabih Harun, Nafs al-Rasul, Akh al-Rasul, Zawj al-Batul, Sayf Allah al-Maslul, Amir al-Barara, Qatil al-Fajara, Dhu l-Qarnayn, al-Hadi, Sayyid al-'Arab, Kashshaf al-Kurab, al-Da'i, al-Shahid, Bab al-Madina, al-Wali, al-Wasi, Qadi Din Rasul Allah, Munjiz Wa'dih, al-Naba' al-'Azim, al-Siraṭ al-Mustaqim, and al-Anza' al-Batin.
"Amir al-Mu'minin" (the Commander of the Faithful) is a title which is, according to Shiite belief, exclusively reserved for Imam Ali (a). Based on narrations, Shiites believe that this title was used for Imam Ali (a) in the time of the Prophet (s) and is exclusive to him. They believe that this title is not only inappropriate to use for other caliphs, it should also not be used for other Imams (a).
It is reported in different sources that he was a little smaller than average height, and had wide black eyes, long and joined together eyebrows, a beautiful light brown face and full beard. His shoulders were wide. Regrading Ali's (a) physical strength, it is reported that all those who fought him were defeated by him. Ibn Abi l-Hadid says, "'Ali's (a) physical prowess was well-known. He was the one who lifted the gate of Khaybar, even when a whole group of the troops could not take it back to its place. He was the one who threw down the idol of Hubal (which was a large idol), from the top of the Ka'ba to the ground. He was also the one who lifted up a huge rock with his hands, while a spring gushed forth beneath it."
Imam 'Ali (a) was born inside the Ka'ba in Mecca on Friday, Rajab 13, in the thirtieth year after the year of the elephant (23 BH/September 28, 600 CE). His birth inside the Ka'ba is widely accepted (Mutawatir) by many Shi'a scholars (including al-Shaykh al-Saduq, al-Sayyid al-Radi, al-Shaykh al-Mufid, Qutb al-Rawandi, and Ibn Shahrashub) and many Sunni scholars (including al-Hakim al-Nishaburi, al-Hafiz al-Ganji al-Shafi'i, Ibn al-Jawzi al-Hanafi, Ibn Sabbagh al-Maliki, al-Halabi, and al-Mas'udi.)
When Ali (a) was 6 years old (17 BH/606 CE), there was a famine in Mecca. Abu Talib had a large family and supporting them was difficult, especially during the famine. Therefore, Prophet Muhammad (s) and his uncle, al-'Abbas, decided to help Abu Talib and his family by taking care of his children. Therefore, al-'Abbas took Ja'far, and Prophet Muhammad (s) took 'Ali (a). Ali (a) would speak of those days fondly:
When the Prophet's mission began in 13 BH/610, Ali (a) was the first man and Khadija (a) was the first woman to have accepted the Prophet's call and believed in him. Ali (a), who was ten years old at the time, would pray with the Prophet (s) on the mountains around Mecca. When the Prophet (s) announced his mission publicly, in the event of Warning the Close Kin, Ali (a) supported him and, in response, the Prophet (s) called Ali his brother, wasi (executer of his will), and successor.
In 7 BH/615, the Muslims were besieged in the valley of Abu Talib by the polytheists and were prohibited from trade and placed under curfew. In this period and in several occasions, Abu Talib ordered Ali (a) to sleep where the Prophet (a) used to sleep in order to preserve the Prophet's life. Shortly after the siege ended, Ali (a) lost his father in 4 BH/619. With the demise of Abu Talib, the situation became more difficult for the Muslims, and the Prophet (s) decided to emigrate to Medina. The Prophet (s) was informed of the conspiracy of the polytheists to murder him on the night he had planned to embark on his emigration, so Ali (a), 23 years old at the time, slept where the Prophet (s) used to sleep so that the Prophet (s) could secretly leave his house, which was under surveillance by the polytheists. A few days later, and after paying the Prophet's (s) debts, Ali (a) emigrated to Medina together with a group of people among whom were his mother Fatima bt. Asad and Lady Fatima (a) the Prophet's daughter. 
When the Prophet (s) reached Quba region on his way to Medina, he waited fifteen days so that Ali (a) joins him. In Medina and after he constructed his mosque, the Prophet (s) set up the formal pact of brotherhood between the Helpers and the Immigrants; however, he chose Ali (a) as his brother. In 2/624, in the Battle of Badr between the Muslims and the polytheists of Mecca, a large number of the latter's troops, including some of the chiefs of Quraysh, were killed by Ali (a). After the battle, Ali (a) at the age of 25 married Fatima (a) the daughter of the Prophet (s), despite the fact that there were several prominent figures who had proposed marriage to her. The Prophet (s) himself solemnized their marriage.
In 3/625, the polytheists of Mecca waged the battle of Uhud against the Muslims to compensate their defeat in the Battle of Badr. In this Battle, Ali (a) was among the few ones who did not flee the battleground and protected the life of the Prophet (s). It is reported that He was severely wounded sixteen times in that battle. Al-Kulayni and al-Tabari mention that the well-known formula "There is no sword but Dhu l-Fiqar and no man of courage but Ali" was said in this battle in praise of Ali (a). In the same year, Ali's (a) first child, al-Hasan (a), was born. 
In 4/626, when Ali (a) was 27, his mother Fatima bt. Asad passed away. Ali's (a) second child, al-Husayn (a), was born in this year. In 5/627, the Battle of Khandaq took place, which ended with the bravery of Ali (a) in killing Amr b. Abd-Wadd. The third child of Ali (a) and Fatima (a), Zaynab (a), was born in the same year.
In 6/628 AH, the treaty of Hudaybiyya was signed between the Prophet (s) and the Quraysh, whose scribe was Ali (a). In this year, Umm Kulthum, Ali's (a) fourth child was born. In the Sha'ban of the same year, the Prophet (s) sent Ali (a) on a preemptive battle against some of the people of Fadak who had planned to support the Muslims' enemies.  In 7/628, the Battle of Khaybar took place. Ali (a) was one of the flag-bearers of the Muslim army, which was able to conquer Khaybar under his leadership. In 8/630, Ali (a), 31 years old at the time, was among the flag-bearers of the Muslim army in the conquest of Mecca. He helped the Prophet (s) destroy the idols in Ka'ba.
In 9/630, the Battle of Tabuk took place, and the Prophet (s) left Ali (a) as his successor in Medina. This was the only battle in which Ali (a) was not present. When certain rumors were disseminated by the Hypocrites as to the reason why Ali (a) was left in Medina, Ali (a) joined the Prophet (s), who had left Medina with the Muslim army, and informed him about the rumors. In response, the Prophet (s) told him, "Aren't you happy that you are to me like Aaron to Moses?" This saying came to be known as the Hadith al-Manzila. In the same year, Ali (a) was sent by the Prophet (s) on the mission to proclaim the first verses of Quran 9 to the polytheists. Ali (a) accomplished the mission in the afternoon of Eid al-Adha. On Dhu l-Hijja 24, 9/April 3,631, the Prophet (s), together with Ali (a), Fatima (a), al-Hasan (a), and al-Husayn (a) engaged in mubahala with a Christian delegation from Najran.
In 10/632, the Prophet (s) send Ali (a) on a mission to call the people of Yemen to Islam. In the same year, the Prophet went on his last pilgrimage to Mecca, and Ali joined him in Mecca from Yemen. After the hajj, on his way back to Medina in an area called Ghadir Khumm, the Prophet (s) proclaimed Ali to be his successor and the executor of his will. This event is known as the Event of Ghadir Khumm. Ali (a) was 33 years old at the time.
The Prophet (s) passed away on Safar 28, 11/May 25, 632, and after his demise, the rightful successor of the Prophet (s) and the leader of the Muslim community, according to the Shia, was Ali (a). However, when Ali (a) was occupied with performing the burial rituals and ceremony for the Prophet (s), a group of the Companions gathered in Saqifa and elected Abu Bakr as the caliph and successor of the Prophet (s). Ali (a) initially refused to pledge his allegiance to Abu Bakr, but he did so afterwards. The Shiite scholars maintain that the allegiance was pledged under compulsion, and some scholars, such as al-Shaykh al-Mufid, hold that the Imam (a) never pledged his allegiance to Abu Bakr. The Shia also maintain that the companions of Abu Bakr invaded Ali's (a) house to force him to pledge allegiance, during which incident Fatima (a) was hurt and had a miscarriage. Abu Bakr also confiscated Fadak, to which Ali (a) objected in defense of Fatima (a). The invasion of the Imam's (a) house resulted in Fatima's (a) illness, and led to her martyrdom in 11/632.
Abu Bakr passed away in 13/634. Before his death, he appointed 'Umar as his successor. In Muharram, 14/March, 635, Umar embarked on a military expedition against the Sasanids. He camped in an area called Sirar, but some prominent figures, including Imam Ali (a), advised him to remain in Medina, so he returned and sent Sa'd b. Abi Waqqas to the battle in his place. Ibn Athir reports that Ali (a) was a judge during the caliphate of Umar, except in its first few years.
In 16/637 (or 17/638), upon Ali's (a) suggestion, Umar set the year of the emigration of the Prophet (s) to Medina as the beginning of the Islamic calendar. In 17/638, Umar led a military expedition to conquer Jerusalem and announced Ali (a) as his successor in Medina. In the same year, after insistence and threatening, Umar married Umm Kulthum the daughter of Imam Ali (a). It is reported that Umar announced Ali (a) as his successor in Medina in 18/639 as well, when he decided to travel to Syria.
When Umar was assassinated in 23/644 and before his death, he appointed a council of six members, including Imam Ali (a), to choose the next caliph. Umar also granted Abd al-Rahman b. Awf a decisive vote in the council. Abd al-Rahman first asked Imam Ali (a) whether he was ready to accept the caliphate with the condition of acting according to the Qur'an and according to the conduct of the Prophet (s), Abu Bakr, and Umar. The Imam (a) refused to accept the condition of acting according to the conduct of the first two caliphs and said, "I hope I will act according to the book of God and the conduct of the Prophet to the extent of my knowledge, capacity, and ijtihad." Abd al-Rahman then asked Uthman the same question; Uthman accepted the condition, and thus became the next caliph after Umar.