For thousands of years, sub-Saharan Africa was a remote and isolated region, cut off from much of the outside world by vast oceans and the Sahara Desert. In the eighth century Muslim caravans reached west Africa, and in the tenth century Arab merchant ships began trading with the Swahili city-states of east Africa (see Chapter 19). These contacts were, for the most part, mutually beneficial to both African rulers and Muslim merchants. Traders sought gold, ivory, exotic foods such as kola nuts, and slaves. Africans, in turn, gained horses, salt, and other manufactured goods and were also introduced to the religion, law, and culture of Islam. Several African societies, such as the Songhay, the Kongo, and the Ndongo, shifted from band level units to larger, more formal kingdoms.

This political evolution was disrupted after the fifteenth century, when Portuguese mariners reached the west coast of Africa. Direct European contact brought rapid and dramatic changes, which profoundly affected all sub-Saharan societies. Some dimensions of that change are:

• Political upheaval. In the Kongo, for example, the Portuguese undermined the authority of the king and even assassinated uncooperative rulers.
• Outright conquest and settlement. Kongo, Ndongo, and south Africa became European settlements that had Africans as the servant class. The Swahili city-states were seized and forced to pay tribute.
• Intertribal warfare. Portuguese slave traders encouraged African slavers to make raids on their neighbors and to resist their own rulers. Coastal Dahomey profited from the slave trade, while inland peoples suffered.
• Economic exploitation. Indigenous economies were corrupted by the trade, exchanging slaves for manufactured goods such as guns and rum.
• Social disruption. Sixteen million, able-bodied young Africans were enslaved between 1600 and 1800, two-thirds of them men. This disruption seriously impacted village and family life, especially in west Africa.