In the early 8th century Arabs invaded India from the North-West region. This Arab invasion in AD 712 was led by Muhammad Bin Qasim a general of the Umayyad caliphate. Invasion on India was part of the policy of Arab expansion during this period.
The rise of Islam in Arabia gave rise to a new political system. The process of expansion which had started after the capture of Mecca by the prophet Muhammad continued after his death.
The Arab expansion was notable for the speed with which it was accomplished. Between AD 633 - 637, Arab conquered West Asia, Jordan Syria, Iraq, Turkey and Persia. They also conquered parts of North Africa and Southern Europe. Between AD 639 - 637, Egypt was also conquered.
By AD 712, the Arabs had entered Spain and were soon making inroads into Southern France. By the 8th Century AD, the Arabs had acquired a core position from Spain to India, connecting the trade of Mediterranean and the Indian Ocean. During the early years of the 8th Century, the Umayyads reached the height of their power. They had created the largest ever Mulsim state that existed.
Arabs were also attracted by the wealth of India. Arab merchants and sailors had brought back stories of great wealth of India. However, the reason for the invasion of Sindh was to avenge the plunder of Arab Ships by pirates of Debol. King Dahir refused to punish the pirates.
Hajjaj the governor of Iraq despatched an army under Muhammad Bin Qasim. He arrived in Sind in AD 712, and besieged Debol which was situated on the sea coast. After crossing the Indus he marched forward. At Rawar, Muhammad Bin Qasim attacked Dahir who was defeated. Arabs killed a large number of fleeing soldiers. Dahir was also caught and killed. Muhammad Bin Qasim now proceeded forward and within a short span he conquered various important places in Sind including Brahmanabad.
The economic life of Sind got disturbed as a result of campaigns of Qasim. A large number of people and merchants had fled from Sind. He had conquered the major portion of Sind up to the lower Punjab. His rule lasted only for two years. However many Arabs settled down in Sind and established relations with the local population. The Arab influence continued for a long period with pockets of Muslim influence established in various parts of Sind.