17. Britain and the United States outlawed the transatlantic slave trade in the early 19th century
In 1807 the United States enacted a law which made the transatlantic slave trade illegal, with the law taking effect on January 1, 1808. Nearly a year earlier, Great Britain outlawed all slave trading within the British Empire. France abolished the trade during its revolution, re-established it in 1802, revoked it again in 1815, and finally abolished it in 1826. Yet slavery continued in the colonies of France and Britain, as well as in the United States. In the latter, a brisk domestic slave trade continued, often by sea between the slave-holding states. The sea was preferred because it was more difficult to escape from a ship than during a forced march on land. Spain and Portugal continued the transatlantic trade, as well as trade between their holdings in the Americas. With so many ships carrying slaves a smuggling trade became inevitable.
Following the end of the Napoleonic Wars Britain and the United States attempted to prevent transatlantic crossings, but they continued. Nearly three million Africans crossed the Atlantic following the abolition of the trade, mainly in ships from Portugal, Spain, and smuggling groups. One famous American smuggler both before and following the outlawing of the trade was Jean Lafitte. Another was James Bowie, later to gain fame at the Alamo. Smugglers did not hesitate to dispose of slaves overboard when encountering authority on the high seas. Following the American and British outlawing of the transatlantic trade, more than 2,000 ships were stopped on the high seas, their African cargoes freed, the ship seized as a prize.