In Europe, led by the Religious Society of Friends (Quakers) and establishment Evangelicals such as William Wilberforce, the Abolitionist movement was joined by many and began to protest against the trade, but until the Haitian revolution, they were successfully opposed by the owners of the colonial holdings. Denmark, which had been very active in the slave trade, was the first country to ban the trade through legislation in 1792 - one year after the start of the victorious insurrection in Saint-Domingue (modern day Haiti). Denmark's legislation only took effect in 1803, as the Haitian Revolution moved towards its final victory. Britain banned the slave trade in 1807], imposing stiff fines for any slave found aboard a British ship, just three years after the final victory of the slave rebellion in Haiti. The Royal Navy, which then controlled the world's seas, moved to stop other nations from filling Britain's place in the slave trade and declared that slaving was equal to piracy and was punishable by death.
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After the total victory of the Haitian Revolution in 1804, the British realised it was a military necessity to prevent the importation of potential African insurgents into the Caribbean. However, in order to maintain the economic competitiveness of their colonies, they were also compelled to induce other colonial and slave-trading powers to do the same. Therefore, the British campaign against the slave trade by other nations was an unprecedented foreign policy effort.
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By 1853, the British government had paid Portugal over three million pounds and Spain over one million pounds in order to end the slave trade.
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Brazil, however, even after its independence, did not agree to stop trading in slaves until Britain took military action against its coastal areas and threatened a permanent blockade of the nation's ports in 1852.