The Rashidun Caliphate (Arabic: الخلافة الرّاشدة, romanized: al-Khilāfat ar-Rāshidah) was the early Islamic polity led by the first four successive caliphs (lit. "successors"): Abu Bakr, Umar, Uthman, and Ali, collectively known as the Rashidun, or "Rightly Guided" caliphs. These early caliphs led the Muslim community (Ummah) from the death of the Islamic prophet Muhammad in 632 CE to the establishment of the succeeding Umayyad Caliphate in 661 CE, and marked the beginning of the transition out of late antiquity into the Near East's Islamic period.
The title Rashidun stems from the Sunni Islamic doctrine that the caliphs were "rightly guided". Endowed with superior piety and wisdom, their era is regarded in Sunni Islam as a "golden age", second only to the lifetime of Muhammad in sanctity and in providing moral and religious guidance. Sunni Muslims consider the "rightly guided" reign of the first four caliphs as a model to be followed and emulated from a religious point of view. The term Rashidun is not used by Shia Muslims, who make up 10–15% of the global Muslim population, as they only consider Ali to have been a legitimate caliph and reject the first three caliphs as usurpers; while Ibadi Muslims only regard the first two caliphs, Abu Bakr and Umar, as rightly-guided caliphs.
The caliphate's first 25 years were characterized by rapid military expansion during which it became the most powerful economic and military force in West Asia and Northeast Africa. By the 650s, in addition to the Arabian Peninsula, the caliphate had subjugated the Levant and parts of Transcaucasia to the north; North Africa from Egypt to the edge of present-day Tunisia in the west; and regions stretching from the Iranian Plateau to parts of Central and South Asia in the east. The caliphate ended after five years of internal strife.
Following Muhammad's death in June 632, Muslim leaders debated who should succeed him. Unlike later caliphates which were ruled by hereditary dynasties, the Rashidun caliphs were either chosen by a small group of high-ranking companions of Muhammad in shūrā (lit. 'consultation') or appointed by their predecessor. Muhammad's close companion and father-in-law Abu Bakr (r. 632–634), of the Banu Taym, was elected the first caliph in Medina and presided over the conquest of the Arabian Peninsula. The only Rashidun caliph not to die by assassination, he was succeeded by Umar (r. 634–644) of the Banu Adi, who was also a close companion and father-in-law of Muhammad. During Umar's reign, the caliphate expanded at an unprecedented rate, conquering more than two-thirds of the Byzantine Empire and nearly the entire Sasanian Empire.
Following the assassination of Umar, Uthman (r. 644–656) of the Banu Umayya, who was a senior companion and son-in-law of Muhammad, was elected caliph. His reign oversaw the completion of the conquest of Persia in 651 and continued the military campaigns into Byzantine territories. Uthman was assassinated in June 656 and was succeeded by Ali (r. 656–661) of the Banu Hashim, the cousin and son-in-law of Muhammad, who moved the caliphate's capital to Kufa. Ali's accession to the caliphate triggered the First Fitna, a civil war ignited by the refusal of Uthman's kinsman from the Umayyad clan and the long-time governor of the Levant, Mu'awiya ibn Abi Sufyan (r. 661–680) to recognize Ali's suzerainty and pledge allegiance to him until Uthman's killers were brought to justice.
After the Battle of Siffin between Ali's Iraqi army and Mu'awiya's Syrian forces, which resulted in a stalemate and inconclusive arbitration, a faction of Ali's erstwhile supporters, known as the Kharijites, seceded and rebelled against both sides, opposing his decision to arbitrate with Mu'awiya. Following Ali's assassination by a Kharijite dissident in 661, Mu'awiya invaded Iraq with his Syrian army and compelled Ali's eldest son and successor Hasan—who had been chosen as caliph in Kufa—to abdicate in his favour. Mu'awiya then entered Kufa and received the pledge of allegiance from the Iraqis, with his suzerainty being acknowledged throughout the Caliphate, before being proclaimed caliph at a ceremony in Jerusalem, thus founding the Umayyad Caliphate.
The Arabic word rāshid (راشد) means "one who has attained the right path or maturity". The expression al-Khulafāʾ ar-Rāshidūn (الْخُلَفاءُ الرّاشِدُونَ) is an honorific title meaning "successors or representatives who have been guided to the right path". This also implies that they were endowed with superior piety and wisdom, and that their era was a "golden age" following Muhammad in holiness, moral and religious guidance.
During the eighth and ninth centuries, there was a diversity of opinions about which caliphs were rāshidūn. After the ninth century, however, the first four caliphs became canonical as rāshidun in Sunni Islam. The Umayyad caliph Umar ibn Abd al-Aziz (r. 717–720) was cited as a fifth rāshidun caliph by the Sunni hadith collector Abu Dawud al-Sijistani (d. 889). Another hypothesis may have included Hasan ibn Ali (c. 625–670) as a fifth rāshidun caliph, because his six-month reign was needed to complete a thirty-year period after Abu Bakr's ascension, which was predicted by Muhammad in a Sunni hadith as the length of the prophetic succession.
In Shia Islam, the temporal and spiritual heritage of Muhammad is represented by the Imams, who (except for the first Imam Ali, who was his son-in-law) were his descendants. The first three Rashidun caliphs are regarded in Shia Islam as having usurped the rights of Ali, and the later Umayyad and Abbasid caliphs are regarded as having usurped the rights of the following Imams.
Ibadism does not see the caliphate as an institution that includes all believers and that must be obeyed. It considers the first two caliphs after Muhammad, Abu Bakr and Umar, as being on the right path; and their successors, including Uthman and Ali, as having strayed into injustice.
According to the traditional account, Muhammad began receiving what Muslims consider to be divine revelations in 610 CE, calling for submission to the one God, preparation for the imminent Last Judgement, and charity for the poor and needy. As Muhammad's message began to attract followers, he was also met with increasing hostility and persecution from Meccan elites. In 622 CE Muhammad migrated to the city of Yathrib (now known as Medina), where he began to unify the tribes of Arabia under Islam, returning to Mecca to take control in 630 and order the destruction of all pagan idols. By the time Muhammad died c. 11 AH (632 CE), almost all the tribes of the Arabian Peninsula had converted to Islam, but disagreement broke out over who would succeed him as leader of the Muslim community.
Among those seeking to be the successor of Muhammad were:
the Muhajirun, senior companions of Muhammad, including those known as "The ten to whom Paradise was promised" (al-ʿashara al-mubashsharūn).
the Banu Hashim; members of the Hashemite clan including Ali and Abbas ibn Abd al-Muttalib, who were the closest blood relatives to Muhammad;
the Ansar; the people of Medina who had sheltered Muhammad and the early Muslims but were now "fed up" with being dominated by refugees from Mecca.
the members of the aristocratic Quraysh tribe, including the powerful Umayyad clan who held a strong position in Mecca and maintained influential commercial and financial ties.
In determining Muhammad's successor, the strong support and companionship given to him from the early years of his prophethood, praise given by Muhammad and the close kinship ties established with him came to the fore as the determining attitude. The first two caliphs gave their daughters to Muhammad in marriage while the next two married with Muhammad's daughters.
(Note that a caliph's succession does not necessarily occur on the first day of the new year.)