As the arab empire declined why did islam continue to spread?

Muslim conquests in the death following Muhammad's death led to the creation of the caliphates, occupying a vast geographical area; conversion to Islam was boosted by missionary activities, particularly those of Imams, who intermingled with local populations to propagate the religious teachings.[1] These early caliphates, coupled with Muslim economics and trading and the later expansion of the Ottoman Empire, resulted in Islam's spread outwards from Mecca towards both the Atlantic and Pacific Oceans and the creation of the Muslim world. Trading played an important role in the spread of Islam in several parts of the world, notably southeast Asia.[2][3]

Muslim dynasties were soon established and subsequent empires such as those of the Abbasids, Fatimids, Almoravids, Seljukids, Ajuran, Adal and Warsangali in Somalia, Mughals in India and Safavids in Persia and Ottomans in Anatolia were among the largest and most powerful in the world. The people of the Islamic world created numerous sophisticated centers of culture and science with far-reaching mercantile networks, travelers, scientists, hunters, mathematicians, doctors and philosophers, all contributing to the Golden Age of Islam. Islamic expansion in South and East Asia fostered cosmopolitan and eclectic Muslim cultures in the Indian subcontinent, Malaysia, Indonesia and China.[4]

As of 2015, there were 2 billion Muslims,[5][6] with one out of four people in the world being Muslim,[7] making Islam the second-largest religion in the world.[8] Out of children born from 2010 to 2015, 31% were Muslim. Babies born to Muslims are expected to outnumber those to Christians by 2035.[9]

the caste system in india is the paradigmatic ethnographic example of caste. it has origins in ancient india, and was transformed by various ruling elites in medieval, early-modern, and modern india, especially the mughal empire and the british raj.it is today the basis of educational and job reservations in india.it consists of two different concepts, varna and jati, which may be regarded as different levels of analysis of this system.

the caste system as it exists today is thought to be the result of developments during the collapse of the mughal era and the british colonial regime in india. the collapse of the mughal era saw the rise of powerful men who associated themselves with kings, priests and ascetics, affirming the regal and martial form of the caste ideal, and it also reshaped many apparently casteless social groups into differentiated caste communities.the british raj furthered this development, making rigid caste organisation a central mechanism of administration

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