According to Bentley and Ziegler, there were three ways in which Islam reached India. Islam started to come to India less than one hundred years after the faith began with Muhammad in Arabia.
Bentley and Ziegler say that the first way in which Islam came to India was via military action. Arab forces entered India on exploratory campaigns “as early as the mid-seventh century (Brief Second Edition, p. 245).” In 711, an expedition of Arabs conquered Sind, in northwestern India. This brought the Umayyad empire into India and, with it, Islam.
The second way that Islam reached India was through trade. Beginning in the 7th century, Muslim merchants dominated trade between India and areas to the west. They formed communities in various Indian cities and spread their faith in that way.
Finally, Islam entered India from a different direction. During the eleventh century, people from Central Asia who spoke Turkish moved from Afghanistan into India. They had converted to Islam earlier and they brought their religion with them.
Thus, Bentley and Ziegler say that Islam entered India in three ways. Two of these were different sets of military invasions from different areas of the world. The other way was through trade.