The rapidity of the spread of Islam (http://www.islam.com/), the relgion of Muhammad and the dramatic suddenness with which the adherents of his creed rose to a position of dominan sovereignity constitute one of the marvels, or it migh be said the miracles of history . No cut and dried explanation that can be offered is felt to account adequately for the astounding facts .But history records not a few other unexplained marvels, we must be content to acknowledge that many thisngs in the Past, as in the past, as in the present, pass man's understanding. Muhammad's fellow citizens at Mecca were so hostile that in AD 622 He was obliged to quit his birthplace znd take his frefuge at Mecca. But within ten years of His life was sufficient to make substantially the sovereign of Arabia and the accepted prophet of the Arabs.Soon after His death in 632 his successors, the early Khalifs (Caliphs), found themselves in conflict with the mighty Persian and Byzantine empires.Nothing could withstand the furious enthusiasmof the Arabs from the desert, beneath whose attack ancient thrones tottered and fell. Within he brief space of eighty years from the prophet's death his Arab followers had become the masters, not only of Arabia, but of Persia, Syria,, western Turkistan, Sind, Egypt, and southern Spain. They carried their new religion with them, and either imposed it on their opponents at the point of the sword, or complled them to ransom their lives by heavy payments. The Indian border lands soon attracted the attention of the Khalifs. The Arabs reached the coast of Makram as early as AD 643. the conquest of Sind was affected by Muhammad bin Qasim in AD 712, and thence forward for centuries that country remained under the rule of Arab.From the begining of the eighth century many Arabs and Muslims of other nations must have settled in Sind and and the neighbouring countries, effecting a marked change in the character of the population. But India proper remained substantially unaffected, although Arab Traders occasionally visited the western kingdoms for business purposes and the Arab chiefs of Sind made several raids on Hindu Territory. The Indian Rajas rarely troubled themselves about events taking place to the Hakra River, then the boundary between Sind and Hind. The The annexation of the Punjab to the Gazni kingdom about AD 1020 by Sultan Mahmud necessarily involved extensive settlement of the of Muslim strangers in that province, although the rest of India continued to be free from their presence.
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From the closing years of the twelfth century, when Muhammad of Ghor began the systematic conquest of the country, a constant stream of Muslim immigrants , continued to flow in ; and during the period of the growth of the Sultanate of Delhi new comers arrived without ceasing.During the decline of the Sultanate from 1340 to 1526 the immigration must have diminished but in the later year it5 received a fresh impetus from the victories of Baur.