Rashidun Caliphate follows Sasanian Empire
The Rashidun Caliphate (Arabic: اَلْخِلَافَةُ ٱلرَّاشِدَةُ, romanized: al-Khilāfah ar-Rāšidah; 632 – 661) was the first caliphate to succeed the Islamic prophet Muhammad. It was ruled by the first four successive caliphs of Muhammad after his death in 632 CE (11 AH). During its existence, the empire was the most powerful economic, cultural, and military force in West Asia.
The caliphate arose following Muhammad’s passing in June 632 and the subsequent debate over the succession to his leadership. Muhammad's close companion Abu Bakr (r. 632–634), of the Banu Taym clan, was elected the first caliph in Medina and he began the conquest of the Arabian Peninsula. His brief reign ended in August 634 when he died and was succeeded by Umar (r. 634–644), his appointed successor from the Banu Adi clan. Under Umar, the caliphate expanded at an unprecedented rate, ruling more than two-thirds of the Byzantine Empire and nearly the entire Sasanian Empire. Umar was assassinated in November 644 and was succeeded by Uthman (r. 644–656), a member of the Banu Umayya clan, who was elected by a six-person committee arranged by Umar. Under Uthman, the caliphate concluded its conquest of Persia in 651 and continued expeditions into the Byzantine territories. Uthman's nepotistic policies earned him vehement opposition from some Muslim generals and he was eventually assassinated by rebels in June 656.
He was subsequently succeeded by Ali (r. 656–661), a member of Muhammad's Banu Hashim clan, who transferred the capital to Kufa. Ali presided over the civil war called the First Fitna as his suzerainty was unrecognized by Uthman's kinsman and Syria's governor Mu'awiya I (r. 661–680), who believed that Uthman was unlawfully killed and his murderers should be punished. Additionally, a third faction known as Kharijites, who were former supporters of Ali, rebelled against both Ali and Mu'awiya after refusing to accept the arbitration in the Battle of Siffin. The war led to the overthrow of the Rashidun Caliphate and the establishment of the Umayyad Caliphate in 661 by Mu'awiya. The civil war permanently consolidated the divide between Sunni and Shia Muslims, with Shia Muslims believing Ali to be the first rightful caliph and Imam after Muhammad, favouring his bloodline connection to Muhammad.The Rashidun Caliphate is characterized by a twenty-five-year period of rapid military expansion followed by a five-year period of internal strife. The Rashidun Army numbered more than 100,000 men at its peak. By the 650s, in addition to the Arabian Peninsula, the caliphate had subjugated the Levant to the Transcaucasus in the north; North Africa from Egypt to present-day Tunisia in the west; and the Iranian Plateau to parts of Central Asia and South Asia in the east. The four Rashidun caliphs were chosen by a small electoral body consisting of prominent members of the Quraysh tribal confederation called shūrā (Arabic: شُـوْرَى, lit. 'consultation').Umar's reign (634–644)
Before dying in August 634 from an illness, Abu Bakr appointed Umar (r. 634–644) as his successor. Upon his accession, Umar adopted the title amir al-mu'minin, which later became the standard title of caliphs. The new caliph continued the war of conquests begun by his predecessor, pushing further into the Sassanian Empire, north into Byzantine territory, and went into Egypt. These were regions of great wealth controlled by powerful states, but the long conflict between Byzantines and Persians had left both sides militarily exhausted, and the Islamic armies easily prevailed against them. By 640, they had brought all of Mesopotamia, Syria and Palestine under the control of the Rashidun Caliphate; Egypt was conquered by 642, and the entire Sassanian Empire by 643.
While the caliphate continued its rapid expansion, Umar laid the foundations of a political structure that could hold it together. He created the Diwan, a bureau for transacting government affairs. The military was brought directly under state control and into its pay. Crucially, in conquered lands, Umar did not require that non-Muslim populations convert to Islam, nor did he try to centralize government. Instead, he allowed subject populations to retain their religion, language, and customs, and he left their government relatively untouched, imposing only a governor (amir) and a financial officer called an amil. These new posts were integral to the efficient network of taxation that financed the empire.
With the bounty secured from conquest, Umar was able to support its faith in material ways: the companions of Muhammad were given pensions on which to live, allowing them to pursue religious studies and exercise spiritual leadership in their communities and beyond. Umar is also remembered for establishing the Islamic calendar; it is lunar-like the Arabian calendar, but the origin is set in 622, the year of the Hijra when Muhammad emigrated to Medina.
While Umar was leading the morning prayers in 644, he was assassinated by the Persian slave Abu Lu'lu'a Firuz. He appointed Suhayb ibn Sinan to lead the prayers.Uthman's reign (644–656)
Election of Uthman
Before Umar died, he appointed a committee of six men to decide on the next caliph and charged them with choosing one of their own numbers. All of the men, like Umar, were from the tribe of Quraysh.
The committee narrowed down the choices to two: Uthman and Ali. Ali was from the Banu Hashim clan (the same clan as Muhammad) of the Quraish tribe, and he was the cousin and son-in-law of Muhammad and had been one of his companions from the inception of his mission. Uthman was from the Umayyad clan of the Quraish. He was the second cousin and son-in-law of Muhammad and one of the early converts of Islam. Uthman was ultimately chosen.
Uthman reigned for twelve years as a caliph. During the first half of his reign, he was the most popular caliph among all the Rashiduns, while in the latter half of his reign he met increasing opposition, led by the Egyptians and concentrated around Ali, who would albeit briefly, succeed Uthman as caliph.
Despite internal troubles, Uthman continued the wars of conquest started by Umar. The Rashidun army conquered North Africa from the Byzantines and even raided Spain, conquering the coastal areas of the Iberian Peninsula, as well as the islands of Rhodes and Cyprus. Also, coastal Sicily was raided in 652. The Rashidun army fully conquered the Sasanian Empire, and its eastern frontiers extended up to the lower Indus River.Uthman's most lasting project was the final compilation of the Qur'an. Under his authority diacritics were written with Arabic letters so that non-native speakers of Arabic could easily read the Qur'an.
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