During the years of 1000-1750 the slave trade in Africa went from tribal traditions to a worldwide trade system, although the effects were good for African economics because of the increase of imported goods, the effects on the African society were highly taxing due to the significant dip in population and demeaning view of Africans by the rest of the world. .
Between the years of 1000-1300 were the first major signs of slavery in Africa, a tribal tradition. Although it was a tradition that had been practiced for many centuries, slave trade between these three centuries was at a much higher magnitude than before. Tribes would go to war amongst one another and take war captives, which they would in turn trade with other tribes for vital goods. Tribes would also have people who were in an extreme amount of debt become slaves who would also be traded with other tribes. Between these three centuries almost the whole of the slave trade was inter-Africa. Most of the outside world was getting their slaves from the Caucasus Mountains and Southern Russia.
During the transition years of 1300-1450 Swahili City-States became the key role in the slave trade. Up until this point most of the slave trade was contained within Africa. But, once city-states were established, a strong and efficient trade route was created. More foreign merchants flowed into the city-states over the next two hundred years, striking deals with the local kings and merchants of trading manufactured items and other goods in exchange for slaves. A majority of these merchants were Muslim merchants who would take these slaves back to their homeland and trade them with other foreign merchant, but near the end of this transition stage European merchants started to engage in trade with the Western kingdoms of Africa (Mali and Songhay) and the Central kingdom of Africa (Kongo). The rise of the African slave trade with Europeans opened a whole new door to worldwide slave trading.
