Beginning in 1787 the English  began campaigning for the abolition of the slave trade. As the slave trade was the product of black Africa itself, the only way the English could abolish the slave trade was by prohibiting English purchase of slaves and by using England's command of the seas to blockade the African ports where the slaves captured by the black African King of Dahomey were loaded onto Portuguese, French, British, and Dutch ships. Once the British closed Dahomey's Gate of No Return at Ouidah by blockading the port, Dahomey's revenues which had equipped Dahomey's army with modern European weapons collapsed, and Dahomey fell to the French in the 1890s just as the 20th century opened.

In 1833 the English Parliament passed the Slavery Abolition Act, which freed slaves in English territories. But it was not until 1851 when the Brazilian slave trade was abolished that the English began blockading the ports of Africa's Slave Coast. Nevertheless, the Dahomey slave trade continued into the 1860s.