Indian Ocean trade Madagascar at this time leaving behind a lasting cultural and genetic legacy. Chinese fleets under Zheng He criscrossed the Indian Ocean during the early part of the 15th century. The missions were diplomatic rather than commercial, but many exchanges of gift and produces were made. The Portuguese under Vasco da Gama discovered a naval route to the Indian Ocean through the southern tip of Africa in 1497–98. Initially, the Portuguese were mainly active in Calicut, but the northern region of Gujarat was even more important for trade, and an essential intermediary in east-west trade. Venetian interests were directly threatened as
Portuguese nationality law to prove that they were descended from Portuguese Jews expelled in 1497, have emigrated to Portugal and acquired citizenship. Nearly 1,800 descendants of Sephardic Jews acquired Portuguese nationality in 2017. By February 2018, 12,000 applications were in process, and 1,800 applicants had been granted Portuguese citizenship in 2017. Portugal allows dual citizenship. Hence, Portuguese citizens holding or acquiring a foreign citizenship do not lose Portuguese citizenship. Similarly, those becoming Portuguese citizens do not have to renounce their foreign citizenship. Although Portugal allows dual citizenship, some countries, such as Japan, do not. Thus, dual Portuguese–Japanese citizens, under Japanese nationality law, must