End of The Rai Dynasty
After the Arabs defeated the Sassanid allies of Persia (641 CE), they prepared for the Islamic conquest of the Indian Subcontinent, an area where Buddhism and Hinduism flourished. In 644, following the Muslim conquest of Persia, the Rashidun Army entered Makran and defeated the army of Raja Rasil in a decisive Battle of Rasil, and annexed Makran and eastern Balochistan. Caliph Umar (634-644), disapproved of any incursion beyond the Indus river and ordered his commander to consolidate their position west of Indus. During the reign of Caliph Uthman ibn Affan (644-656), Muslims captured Qanzabil in northern Sindh, which held a major military garrison of the Rai Dynasty, which from that point served as the eastern-most garrison town for the Rashidun Army. In 662, during the Ummayad Caliphate, Qanzabil was retaken by the Rai kingdom.
The Rai Emperors fought numerous battles with Muslims, resisting the north-west Subcontinent invasion. The numerous wars drained the Rai economy and the Empire disappeared. Dr. R. S. Sharma suggests, in Shahnameh, that the dynasty retreated to the Himalayan mountains with Hepthalite allies during the Islamic conquest, and that Rai history from that point was lost to Indian literature.
According to Chachnama, the last Rai emperor Rai Sahasi II died through illness without any issue. By that time Chach was in complete control of the affairs of the kingdom. Rai Sahasi's wife, Suhanadi, was attracted to Chach and asked for his sexual favors, initially resisted by Chach. However, when Rai Sahasi II was near to death, Suhanadi explained to Chach that the kingdom would pass to other relatives of the dying king in absence of any direct heir to the kingdom. Consequently, they kept secret the news of the king's death until claimants to the throne were killed through conspiracy. Following this, Chach declared himself ruler and later married Suhandi. This ended the Rai Dynasty and began the dynasty of Chach. Six months after death of Rai Sahasi his brother, Rana Maharath of Chittor, challenged Chach in combat, claiming to be rightful ruler of the Rai Dynasty. Chachnama states that Maharath was killed as the two engaged in a duel, in which it was forbidden to mount a horse or any other animal. During the duel Chach mounted a horse in order to kill his rival.
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