The period from the 8th to 12th century in political life in India is particularly dominated by the presence of large number of states. The bigger ones tried to establish their supremacy in northern India and the Deccan. The main contenders in this struggle for supremacy were the Pratiharas, the Palas and the Rashtrakutas. In the south the most powerful kingdom to emerge during this period was that of the Cholas. The Cholas brought about the political unification of large parts of the country but the general political picture was that of fragmentation particularly in northern India. It was in this period that India's contact with the new religion of Islam began. The contacts began late in the 7th century through the Arab traders.
Later in the early 8th century the Arabs conquered Sind. In the 10th century the Turks emerged as a powerful force in Central and West Asia and carved out kingdoms for themselves. They conquered Persia but their lives were richly influenced by Persian culture and tradition. The Turks first invaded India during the late 10th and early 11th century and Punjab came under Turkish rule. Another series of Turkish invasions in the late 12th and early 13th century led to the establishment of the Sultanate of Delhi. Within a few centauries after the rise of Islam in Arabia it became the second most popular religion in India with followers in every part of the country.
The establishment of the Sultanate marked the beginning of a new phase in the history of medieval India. Politically it led to the unification of northern India and parts of the Deccan for almost a century. Its rulers almost from the time of the establishment of the Sultanate succeeded in separating it from the country from which they had originally come. The sultanate disintegrated towards the end of the 14th century leading to the emergence of a number of kingdoms in different parts of the country. Some of these like Bahmani and Vijaynagar kingdoms became very powerful. In society new social groups -the Turks, the Persians, the Mongols and the Afghans besides the Arabs who had settled in India. There were important changes in economic life also. Trade and crafts received a stimulus and many new towns arose as centres of administration, trade and crafts. New elements of technology were also introduced during this period.