What is History of Islam?
{{Islam}} The '''History of Islam''' began in [[Arabia]] when [[Muhammad]] was given the revelation of the [[Quran]] by the angel [[Gabriel]] in the [[7th century]]. Muslim history and the historical development of [[Islam]] has affected political, economic, and military trends both inside and outside the [[Muslim world]]. As with [[History of Christianity|Christianity]], the concept of an ''Islamic world'' is useful when one looks at different periods of human history. ==Early Muslim history== After Muhammad died, the Arab Muslim leadership was assumed by [[Abu Bakr]]. He was followed by [[Umar]], [[Uthman ibn Affan]], [[Ali]], and [[Mu'awiya I]], who established the [[Umayyad Caliphate]]. Under these caliphs, Islam became one of the most important religions in the world. Under Umar, more than two thirds of the [[Eastern Roman Empire]] was conquered by the Arab Muslims. Umar also started the [[Muslim calendar]]. The Arab Islamic empire reached its largest geographical extent under the Umayyad Caliphate.<ref>{{cite book | url=https://books.google.com/books?id=D1tmDwAAQBAJ&dq=islamic+empire+largest+extent+umayyad&pg=PA63 | title=The Islamic Empire | isbn=9781420508024 | last1=Nardo | first1=Don | date=12 September 2011 | publisher=Greenhaven Publishing LLC }}</ref> ==Islamic civil wars== ===The First ''Fitna''=== The first civil war in Islam, also known as the ''First Fitna'' broke out in Islam during the rule of the fourth caliph Ali and lasted throughout his caliphate. The third caliph Uthman ibn Affan had been murdered by rebel Muslim groups who had political motives. After Ali took over, the most important problem he faced was that of punishing those responsible for murder. However many people felt that before accepting the position of the caliph, Ali should have focused his attention on finding and punishing the murderers. A group of people led by Muhammad's wife [[Aisha]], her brothers in law [[Talhah]] and [[Zubair ibn al-Awam]] refused to recognize Ali's caliphate. They instead raised an army which met