As the Islamic community grew, so did the internal differences, the beginnings of which already existed at the time of Mohammed. The rapid expansion of the Muslim Arabs after his death led to new contrasts and outside influences. Formally, this led to the outbreak of the political conflict over the legitimate ruler, but behind it concealed further, even religious, differences. The murder of Othman, the 3rd caliph, in 656 initially divided the Islamic community into three parts: followers of Ali Ibn Abi Talibs, followers of the Umayyad governor of Syria and later Umayyad caliph, Moawija, and followers of an aristocratic group from Medina around Mohammed Widow Aisha. After the latter group had been defeated by Ali Ibn Abi Talib in 656, it came to a confrontation with Moawija, as a result of which Ali was recognized by an arbitration tribunal. Parts of his army opposed this and left it. This is how the first political-religious group in Islam came into being, the Charidjites, who murdered Ali Ibn Abi Talib in 661. After his death, various groups appeared again and again to pay homage to leaders in his successor. From these went since the 9th / 10th. In the 19th century, the Shiites emerged, who form several subgroups, while the Sunnis represented the majority of Muslimsfor their part have trained different directions and schools of law (madhhabs).
According to sportingology.com, Islam acquired a truly universal character in the course of its intellectual structuring, while initially it was largely restricted to ethnic Arabs. The basis for this was the different interpretation of the Arabic text of the Koran, which has been uniform since 656 and was unanimously recognized as the word of God, and the prophetic tradition (hadith), for the Shiites also the tradition of the imams. Further Islamic literature was based on these authoritative text complexes. As methods of accommodation (adaptation) of Islamic teaching content to new circumstances, the conclusion by analogy and various individual doctrinal interpretations (Idjtihad). Theological considerations were not least influenced by philosophical and theological ideas from the Christian environment. Under the first Abbasid caliphs, the Mutasilites, a theological movement that united strongly individualized thinkers, gained in importance in the dispute with representatives of a traditional Sunniism until they were pushed back under the caliph al-Mutawakkil (* 822, † 861; caliph from 847) became. Religious philosophical ideas were widespread in elitist circles (Farabi, Ibn Sina). Up until the end of the Middle Ages, there were strong encyclopedic tendencies among Islamic scholars (e.g. Biruni, Sujuti). In the 9th century, ascetic currents gave rise to Sufi schools that emphasized the spiritual and individual side of Islam (Sufism). By the 9th century, important foundations of Islam were laid that had a decisive influence on its further development. In the 10th and 11th centuries influenced Shiite – v. a. Ismaili – currents strong the spiritual life in Islam, promoted the advance of the Turkish Seljuks Sunniism, which has increasingly become the majority tendency in Islam since the second half of the 11th century. In addition to the directions mentioned, other currents always worked in parallel in Islamic intellectual history: regionally and locally rooted approaches, primarily formalistic, legalistic and spiritually based religious positions, diverse popular expressions of Islamic religiosity (popular Islam). Again and again reformers and personalities with pronounced individuality and religious charisma appeared; notable examples are Ghazali, Ibn al-Arabi and Ibn Taimija. Sufi brotherhoods spread from the end of the 12th century as the main organizational form of Islam in relation to its ascetic-mystical base, which includes a large number of Muslims. The brotherhoods have made a decisive contribution to the spread and consolidation of Islam within and outside of its dominion. In the following centuries, strong tendencies towards institutionalization and spiritual and ritual traditionalization developed within Islam. B. since the 13th century in the Mamluk Empire and since the 15th century in the Ottoman Empire.
Since the middle of the 7th century, Islam lacked a central, generally recognized religious authority in an individual or body. It was intrinsically multifaceted and pluralistic. The tense relationship between the politico-military rule, which was religiously legitimized and was supposed to protect religion, and the normative and spiritual currents widespread among Muslims (especially scholars), whose representatives rely on their normative and orienting, also ran through its history Positions persisted and criticized the pragmatism of the rulers. In the legal field, these contradictions caused tensions, especially between the legal teachings of the scholars, who could not implement them, and the often different and arbitrary legal and political practice of the powerful, often of foreign origin and not very educated; de facto, in the broadest sense, these only exceptionally adhered to the norms of Islam. The unity of political rule (state) and religion existed in the history of Islam as an unfulfilled requirement that was revived in the 20th century.
With the empires of the Ottomans in the Mediterranean, the Safavids in the Iranian area and the Mughals in India (Mughal Empire), rulers that considered themselves Islamic existed for centuries. Under the Safavids, the determined expansion of Shi’aism in Iran began in the 16th century. The political contradictions and military conflicts between the Safavids and the Ottomans were also given a religious orientation, which was expressed in the contrast between Shiites and Sunnis.
Among the various efforts to adapt Islam to new conditions, the strictly traditionalist movement of the Wahhabis in the north of the Arabian Peninsula gained particular importance at the end of the 18th century. It was based on the literal interpretation of the Koran, followed largely the tradition in the manner of the Hanbalites and came out against all forms of non-scriptural religiosity. Their ideas found supporters in large numbers among the Sunnis as a whole – also in the form of derived interpretative approaches.