building of European origin to have been planned and executed in Sub-Saharan Africa. Upon its completion, Elmina was established as a proper city. Azambuja was named governor, and King João added the title "Lord of Guinea" to his noble titles. São Jorge da Mina took on the military and economic importance that had previously been held by the Portuguese factory at Arguim Island on the southern edge of Mauritania. At the height of the gold trade in the early sixteenth century, 24,000 ounces of gold were exported annually from the Gold Coast, accounting for one-tenth of the world's supply. The new fort, signifying the permanent involvement of Europeans in West Africa, had a considerable effect on Africans living on the coast. At the urging of the Portuguese, Elmina declared itself an independent state whose Governor then took control of the town's affairs. The people of Elmina were offered Portuguese protection against attacks from neighbouring coastal tribes, with whom the Portuguese had much less genial relations (even though they were friendly with the powerful trading nations in the African interior). If any locals attempted to trade with a nation other than Portugal, the Portuguese reacted with aggressive force, often by forming alliances with the betraying nation's enemies. Hostility between groups increased, and the traditional organization of native societies suffered, especially after the Portuguese introduced them to fire-arms, which made the dominance of the stronger nations easier. Trade with the Europeans helped make certain goods, such as cloth and beads, more available to the coastal people, but European involvement also disrupted traditional trade routes between coastal people and northern people by cutting out the African middlemen. The population of Elmina swelled with traders from other towns hoping to trade with the Portuguese, who gradually established a West African monopoly. West African slave trade From the outset, the Portuguese authorities determined that São Jorge da Mina would not engage directly in the slave trade, as they did not wish to disrupt the gold mining and trade routes of its hinterland with the wars necessary to capture free people and enslave them. Instead, the Portuguese had captives shipped to São Jorge da Mina from elsewhere, notably the Slave Coast (Benin) and São Tomé. São Jorge da Mina served as a transshipment entrepôt. By the seventeenth century, most trade in West Africa concentrated on the sale of slaves. São Jorge da Mina played a significant