"The first part of South Asia to be cleansed of Hinduism was Afghanistan. The 10 th century saw a life-and-death struggle there between Muslim invaders and the local Hindu population and dynasty. In this case, the replacement was not just religious, of Hindus by Muslims, but also ethnic, viz. of Indo-Aryans by Iranians. The fact of an at least partial physical replacement of the native population by invaders is attested by the linguistic shift. Until then, in much of the present-day Pashtu-speaking region of Pakistan and Afghanistan, an Indo-Aryan Prakrit was spoken (remember how the Sanskrit grammarian Panini was a native of Peshawar). It was replaced with Pashtu, an Iranian language."