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
Trade route from the Varangians to the Greeks opened more lucrative routes from Europe to the Orient through the Crusader states of the Middle East. By that time, Rus' had strengthened its commercial ties with Western Europe, and the route from the Varangians to the Greeks gradually lost its significance. For a related military route, see Muravsky Trail. Trade route from the Varangians to the Greeks The trade route from the Varangians to the Greeks (, , , , ) was a medieval trade route that connected Scandinavia, Kievan Rus' and the Eastern Roman Empire. The route allowed merchants along its length to establish a direct prosperous trade