Raja Dahir, also known as Dahir Sen, was the the last Hindu King of Sindh. He belonged to the Pushkarna Brahmin Community. His Kingdom had been conquered by the Arab General, Muhammad bin Qasim.
Chach Nama is the oldest record of Arab conquest of Sind. The Arabs had become a vigorous militant race. The conquests of Arabs spread far and wide over Egypt, Syria, Palestine, and Persia. The Arab conquest of Sind that occured in the first quarter of the 8th century.
The Arabs invaded Sind at the instance of Hajjaj, the Governor of Iraq. One of the Arab ships was plundered near the Sind coast and the Arab governor demanded compensation from Raja Dahir, King of Sind. Raja Dahir refused and hence the Arab invasion. The first two Arab attempts were repulsed with success. But the third expedition was a much more serious undertaking. It was led by a young but exceptionally vigorous general named Mahammad bin Qasim.
As usual, Raja Dahir came out and fought valiantly. But his valor could not save him. Some of his generals were won over by the Muslims. His enemies were overwhelmingly superior in number. In the end he was defeated. Raja Dahir died a hero’s death fighting on the field of battle. His worthy widow carried on the battle for some time, but finding that defeat was inevitable, she preferred death to disgrace and burnt herself alive, along with her female attendants. Kasim entered the capital and brought the whole of Sind under Muslim authority (712 A.D.)
Nature of Arab rule—its effects: The conquerors, however, were not vindictive. They showed toleration and even generosity towards the vanquished. They respected the manners, customs, religions, and laws of the Hindus and did not interfere with them. The Arab conquest did not spread beyond Sind.