The East African coast had known slavery for centuries. But under Omani rule, the trade expanded to industrial scale. Enslaved people were captured in the interior of Africa, marched to the coast in chains, and shipped to Zanzibar and the Arabian Peninsula. Mombasa became a transit point in a trade that destroyed communities across what would become Kenya, Uganda and Tanzania. Families were separated, villages were burned, and entire regions were depopulated. The human cost of the coastal trade economy was being paid in flesh.