In 1634, the Mughal emperor extended his hospitality to the English traders to the region of Bengal, and in 1717 completely waived customs duties for the trade. The company's mainstay businesses were by then cotton, silk, indigo dye, saltpetre, and tea. The Dutch were aggressive competitors and had meanwhile expanded their monopoly of the spice trade in the Malaccan straits by ousting the Portuguese in 1640–41. With reduced Portuguese and Spanish influence in the region, the EIC and Dutch East India Company (VOC) entered a period of intense competition, resulting in the Anglo-Dutch Wars of the 17th and 18th centuries.