How Buddhists Help Muslims Conquer Sindh
At the time of the Arab conquest, Sindh was about evenly split between Hindus and Buddhists. The more urbanized Lower Sindh had a Buddhist majority while Upper Sindh had a Hindu majority. By 1911, Hindus were a quarter. In 711 AD, most of the important administrative posts were held by Buddhists. They were against the Brahmin domination of their country, so, they voluntarily joined hands with the foreign invader Mohd. Bin Qasim. The Buddhists converted voluntarily to regain their lost trading power.
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