Why Nations Fail: The Origins of Power, Prosperity, and Poverty

now the capital of Angola. During this time, the trans-Saharan slave trade was still larger, with probably about 550,000 Africans moving north as slaves. In the seventeenth century, the situation reversed. About 1,350,000 Africans were sold as slaves in the Atlantic trade, the majority now being shipped to the Americas. The numbers involved in the Saharan trade were relatively unchanged. The eighteenth century saw another dramatic increase, with about 6,000,000 slaves being shipped across the Atlantic and maybe 700,000 across the Sahara. Adding the figures up over periods and parts of Africa, well over 10,000,000 Africans were shipped out of the continent as slaves.
    Map 15 ( this page ) gives some sense of the scale of the slave trade. Using modern country boundaries, it depicts estimates of the cumulative extent of slavery between 1400 and 1900 as a percent of populationin 1400. Darker colors show more intense slavery. For example, in Angola, Benin, Ghana, and Togo, total cumulative slave exports amounted to more than the entire population of the country in 1400.
    The sudden appearance of Europeans all around the coast of Western and Central Africa eager to buy slaves could not but have a transformative impact on African societies. Most slaves who were shipped to the Americas were war captives subsequently transported to the coast. The increase in warfare was fueled by huge imports of guns and ammunition, which the Europeans exchanged for slaves. By 1730 about 180,000 guns were being imported every year just along the West African coast, and between 1750 and the early nineteenth century, the British alone sold between 283,000 and 394,000 guns a year. Between 1750 and 1807, the British sold an extraordinary 22,000 tons of gunpowder, making an average of about 384,000 kilograms annually, along with 91,000 kilograms of lead per year. Farther to the south, the trade was just as vigorous. On the Loango coast, north of the Kingdom of Kongo, Europeans sold about 50,000 guns a year.

    All this warfare and conflict not only caused major loss of life and human suffering but also put in motion a particular path of institutional development in Africa. Before the early modern era, African societies were less centralized politically than those of Eurasia. Most polities were small scale, with tribal chiefs and perhaps kings controlling land and resources. Many, as we showed with Somalia, had no structure of hierarchical political authority at all. The slave trade initiated two adverse political processes. First, many polities initially became more absolutist, organized around a single objective: to enslave and sell others to European slavers. Second, as a consequence but, paradoxically, in opposition to the first process, warring and slaving ultimately destroyed whatever order and legitimate state authority existed in sub-Saharan Africa. Apart from warfare, slaves were also kidnapped and captured by small-scale raiding. The law also became a tool of enslavement. No matter what crime you committed, the penalty was slavery. The English merchant Francis Moore observed the consequences of this along the Senegambia coast of West Africa in the 1730s:
    Since this slave trade has been us’d, all punishments are changed into slavery; there being an advantage on such condemnations, they strain for crimes very hard, in order to get the benefit of selling the criminal. Not only murder, theft and adultery, are punished by selling the criminal for slave, but every trifling case is punished in the same manner.
    Institutions, even religious ones, became perverted by the desire to capture and sell slaves. One example is the famous oracle at Arochukwa,in eastern Nigeria. The oracle was widely believed to speak for a prominent deity in the region respected by the major local ethnic groups, the Ijaw, the Ibibio, and the Igbo. The oracle was approached to settle disputes and adjudicate on disagreements. Plaintiffs who traveled to Arochukwa to face the oracle had to descend from the town into a gorge of the Cross River, where the oracle was housed in a tall cave, the front of which was lined with human skulls. The priests of the oracle, in league with the Aro slavers and merchants, would dispense the decision of the oracle. Often this involved people being “swallowed” by the oracle, which actually meant that once they had passed through the cave, they were led away down the Cross River and to the waiting ships of the Europeans. This process in