>Another problem one encounters is Spencer's pivotal assumption which is crucial to the validity of his whole argument. His thesis assumes that as the early Arab-Muslims conquered the vast territories of the Byzantine and Persian Empires, they would have made an instant top-down (A-Z) transformation of the whole North Africa and Near & Middle East. That is to say, the Arab-Muslims would have instantly started minting their own coins, constructing architectural monuments, transforming administrative practises, altering trade patterns, modify agricultural norms, changed the administrative language to Arabic, and so forth. In doing so, they would have left ample archaeological evidence for their religious beliefs. It is only by constructing a grand "this is what we would expect if…" assumption, which builds up our expectation, that he can then justify his en-silencio thesis when the evidence doesn't live up to the unrealistic expectation.
>Those acquainted with scholarship in the field appreciate however that until the second fitnah, which saw Umayyad Caliph Abdul' Malik ibn Marwan rise to power in 685 CE, the Arab-Muslims conquerors had a rather light footprint. At least three things contributed to the early obscurity of the Arab-Muslims. Firstly, the Arab-Muslims lived in garrisons towns such as Homs and Kufa on the outskirts of the urban centres and were uninterested in mingling with the general populous. Secondly, there lack of material expertise precluded their proclamation of their religion in media such as coins or architecture. Thirdly, the earliest period of Islam saw major internal upheavals which precluded the development of a stable bureaucratic state/empire. The Muslims were themselves engaged in theological and political upheavals which meant that much of the early Arab-Muslims energy and resources went towards internal resolutions instead of outward propagation. These three reasons, among others, delayed the public expression of Islam for the first fifty years. The events leading to `Abd al-Malik's Caliphate would mark the first ostensible attempts of Muslims to proclaim their religion Abdullah ibn Zubayr's challenge to the caliphate, the kharaji rebellion, and `Abd al-Malik's success to leaderships brought a lot of changes. His reign marked a number of significant changes including the minting of fully Islamic coins, the formation of a professional standing army, Arabic as the lingua franca, the centralization taxes and modified trade routes. Following AD 685, virtually all coins, papyri, tombstones, seals, and most architectural monuments have overt Islamic references. The best documentary witness to this slow gradual transformation is in the coinage. The earliest Islamic coins were cheap Byzantine and Sasanian prototypes. The iconography remained the same. The only way you would know it was an Islamic coin was the inscribing of `bismillah', `jayyid', `ja'iz', `dayyib' or some other small Arabic inscription. Other times, this inscription will be accompanied the removal of the cross. This process continued until the time of Abdul Malik when the Arab-Muslims developed one centralized administration to mint their own coins. The final Islamic stage of coinage was epigraphic coins with Qur'anic calligraphy and, of course, no imagery. This was a gradual process with many bumps along the way.
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