Transatlantic Slave Trade

Between 11. 7 and 12. 5 million Africans were exported from Africa during the transatlantic slave trade, according to historical estimates. ^[1] Around 10. 5 to 10. 7 million actually arrived in the Americas. ^[2] That gap represents something staggering: approximately 1. 5 to 2 million Africans died during the Middle Passage alone. ^[3]

Yet the dying began before ships ever left port. Between 15 to 30 percent of enslaved Africans perished during the march to coastal ports or while confined there waiting to board. ^[4] For every 100 people who reached the New World, an estimated 40 had already died in Africa or crossing the Atlantic. ^[5] Mortality rates during the Middle Passage typically ranged from 15 to 20 percent, driven by endemic diseases, epidemic outbreaks, and starvation aboard overcrowded ships. ^[6]

The scale intensified over time. Slave exports grew from about 36,000 per year in the early eighteenth century to nearly 80,000 per year by the 1780s. ^[5] By 1750, slave ships commonly carried at least 400 people, with some holding over 700. ^[7] Each figure represented a human being torn from their home and forced into unimaginable conditions.

The millions extracted left entire regions devastated. Significant population depletion occurred in specific African regions due to the export of millions of people, primarily young adults. ^[8] That depletion wasn't uniform—the Bight of Biafra emerged as a more significant region of slave export than previously thought, with its involvement beginning several decades earlier. Understanding these regional patterns reveals how deeply the trade reshaped African societies, draining populations of working-age people at a scale that reverberated across generations.

The wealth flowing into European port cities reshaped entire economies. Bristol, Nantes, and Lisbon accumulated immense capital through the slave trade, enriching merchants and financing the rise of European commerce. ^[4] But the trade's impact extended far beyond balance sheets. It created lasting human geographies across the Atlantic. African diaspora populations became culturally distinct communities, concentrated especially in Brazil and the Caribbean, where they synthesized African heritage with new realities. ^[9] These communities became the demographic and cultural foundation of entire regions, reshaping the Americas in ways that persist today. When we consider how the violent extraction of 12 million people transformed not just individual lives but the very structure of Atlantic societies—both African and American—we confront a history whose consequences remain woven into our present.

Thanks for listening to this VocaCast briefing. Until next time.