Saqifah,(Arabic: السقيفة) also known as Saqifat Bani Sa'ida or Saqifa Bani Saeda (Arabic: سقيفة بني ساعدة), was a roofed building used by the tribe, or banu, of Sa'ida, of the faction of the Khazraj, of the city of Medina in the Hijaz, northwestern Arabia.
Significance of Saqifah
On the day that Muhammad died, June 8 in 632 CE, the Muslims originally from Medina, the Ansar, gathered in the saqifah to discuss the future & leadership of the Muslims. There were two tribes of the Ansar, the Khazraj and the Aws; both were present. However, the Muslim emigrants from Mecca, the Muhajirun, had not been notified of the gathering. When Muhammad's companions, Abu Bakr and Umar learned of the gathering, they rushed to the meeting. After a tumultuous debate, the details of which are highly contested, those who gathered there gave their allegiance, or bayah, to Abu Bakr as the new leader of the Muslims.
The name of the house is used as shorthand for the event, or the gathering, which was a crucial turning point in the history of Islam. There were some Muslims who felt that Ali ibn Abi Talib, Muhammad's cousin and son-in-law, should have been the new leader. They initially refused to take the oath to Abu Bakr and were known as the Shi'at Ali, or followers of Ali, even though that Ali himself didn't take the oath. Over time, disaffection with the government of the caliphs, strengthened the ranks of the Shi'at Ali. This eventually led to the separation of the Muslim community into the Sunni and Shi'a traditions. Sunnis believes that Abu Bakr, first converter to Islam, Muhammad’s closest companion, adviser and Mohammed's father-in-law, is the successor of Mohammed, because he was the one had been appointed by the prophet to led Muslims in their prayers at Prophet's Holy Mosque at the time of the prophet's illness . Shia believes that Ali and his descendents had a divinely ordained right to lead the community.
Ibn Ishaq's account
According to this account, after the death of Muhammad the Ansar gathered at the Bani Sa'ida's saqifah while the closest relatives of Muhammad, Fatima and Ali and their relatives, were preparing Muhammad's body for burial. Abu Bakr and Umar were sitting with some of the Muhajirun, the emigrants from Mecca. Having heard that the Ansar were meeting, they went to join them. There, Abu Bakr addressed the Ansar.
Abu Bakr argued that only a leader from the Quraysh, Mecca's leading clan, could keep the community intact. Only the Quraysh were universally recognized as a noble clan, worthy of leadership. He suggested that the meeting choose either Umar or Abu Ubayda (both Quraysh) as a leader.
One of the Ansar suggested that the Ansar should choose a leader for themselves and the Meccans should choose another for themselves. The meeting became loud and unruly. Umar is reported to have said that he feared that the unity of the Muslim community would dissolve then and there. So he seized Abu Bakr's hand and loudly swore the bay'ah to him as the leader of the Muslims. The Muhajairun followed his lead and then the Ansar. One man, Sa'd ibn 'Ubada, the leader of the Khazraj faction of the Ansar, protested. Umar's words, as reported to Ibn Ishaq, were, "we jumped on Sad ibn Ubada and someone said we killed him. I said, 'God kill him.'
The next day, the Muslim community of Medina gathered for prayers and Umar spoke, praising Abu Bakr and urging the community to swear allegiance to him. Ibn Ishaq says that the bulk of the community did so. However, there were some who dissented, namely Ali and his supporters.
According to Madelung's book The Succession to Muhammad, Umar later described the event as a falta, a precipitate arrangement (p. 30).
Similarly, according to one hadith, or oral tradition, recorded by Bukhari, Umar is reputed to have said, I have been informed that a speaker amongst you says, 'By Allah, if 'Umar should die, I will give the pledge of allegiance to such-and-such person.' One should not deceive oneself by saying that the pledge of allegiance given to Abu Bakr was given suddenly and it was successful. No doubt, it was like that, but Allah saved (the people) from its evil, and there is none among you who has the qualities of Abu Bakr. Remember that whoever gives the pledge of allegiance to anybody among you without consulting the other Muslims, neither that person, nor the person to whom the pledge of allegiance was given, are to be supported, lest they both should be killed. 
The events of Saqifah are only some of the issues involved in the Succession to Muhammad. See that article for a broader discussion.
- Guillaume, A. The Life of Muhammad, Oxford University Press, 1955
- Madelung, W. The Succession to Muhammad, Cambridge University Press, 1997