what source you need.... before those Muslim attacks ppl in the region we Buddhists or Hindus, by hook or by crook they were converted to islam.
Check: http://en.wikipedia.org/wiki/Pakistan
"In 712 CE, the Arab general Muhammad bin Qasim[10] conquered Sindh and Multan in southern Punjab, setting the stage for several successive Muslim empires including the Ghaznavid Empire, the Ghorid Kingdom, the Delhi Sultanate and the Mughal Empire. During this period Sufi missionaries played a pivotal role in converting a majority of the regional Buddhist and Hindu population to Islam. "
