The Portuguese explorer Vasco da Gama reached Mombasa in 1498. The Portuguese did not intend to found settlements, but to establish naval bases that would give Portugal control of the Indian Ocean. After decades of small-scale conflict, Arabs from Oman defeated the Portuguese in Kenya. Under Seyyid Said, the Omani sultan who moved his capital to Zanzibar in 1840, the Arabs set up long-distance trade routes into the interior. The dry reaches of the north were lightly inhabited by seminomadic pastoralists. In the south, pastoralists and cultivators bartered goods and competed for land as long-distance caravan routes linked them to the Kenyan coast on the east and to the kingdoms of Uganda on the west.