Buddhism in western India appears to have been vitally linked to the mercantile sector of the economy. Prior to the conquest of Sind and neighbouring regions of India by the Arabs in 711, the merchants of this region, majority of whom were Buddhists from different urban centres, derived their livelihood largely from commercial activities directly linked to the inland as well as maritime Silk Road. After the disruption of the land route of the Silk Road, these traders were able to continue their commercial activities through the Indus River and also through the Arabian Sea. However, when the Arabs began controlling commercial activities in the Arabian Sea, the Buddhist traders of western India began facing various kinds of difficulties. Their situation became somewhat precarious after Sind and surrounding regions of western India were annexed into the Arab empire. It has been suggested that this changed situation resulted in quick conversion of Buddhists of Sind to Islam. In this paper, an attempt shall be made to show that incorporation of Sind and surrounding regions of western India into the rapidly expanding maritime trade empire of the Arabs had important implications for Buddhism. With their long history of trade relationships with Central Asia and China, the urban, mercantile Buddhists of Sind appear to have felt that collaboration with the Arabs would open commercial opportunities for them in the Arab eastern front. And also would indirectly help their religion. In other words, they appear to have had good reason to perceive that their mercantile interests would be better served under an Arab trade empire (perhaps one allied with Tibet) than under an isolationist Brāhmaṇa dynasty with little interest in a regularized inter-regional commerce. While the inter-regional commerce cycled through Sind did revive during the Arab period, it was a trade with several critical, interrelated differences, at least from the perspective of the mercantile Buddhists. The Buddhist ability to process the articles of inter-regional trade were affected by both the decline in their control of this commerce and the competition offered by the new Arab facilities. Muslims displaced Buddhists as the dominant urban, mercantile class in Sind and the pan-Islamic international trade network to which Sind became linked by conquest was controlled mostly by the Muslim mercantile bourgeoisie. Discriminatory customs regulations further diminished the ability of the Buddhist merchants of Sind to compete equally with Muslims in large-scale interregional commerce. As a result of these factors, Sindi Buddhist merchants found it increasingly difficult to compete with Muslim merchants on an equal footing in the revived commerce.