The first slaves were captives taken in war and most slaves appear to have been the property of kings, priests and temples, and only a relatively small proportion were in private possession, which does not This is not the case for the transatlantic slave trade. . The Arab Zanj and Bantu slave trade in South East Africa is one of the oldest slave trades, slaves were thought to be sold from the Zanzibar slave market to the Somali coast. Zanj taken as slaves to the Middle East were often used for heavy agricultural work. As the plantation economy boomed and Arabs became wealthier, farming and other manual labor were considered demeaning. Male slaves were often employed as servants, soldiers, or laborers, while female slaves had long been traded in Middle Eastern countries and kingdoms by Arab and Oriental traders as concubines and servants. Legally, Bantu slaves were devalued. Somali social mores strongly discouraged, censored, and looked down upon any type of sexual contact with Bantu slaves. David Livingstone, a Scottish missionary explorer, wrote about the slave trade in the African Great Lakes region, which he visited in the mid-19th century.