There is debate among historians over which factors were the most important in bringing about the end of the transatlantic slave trade. These included a number of factors.
In the 1790s public opinion supported banning the slave trade. Petitions and the boycott of West Indian sugar attracted hundreds of thousands of supporters.
There is some evidence that the slave trade was becoming less profitable. The price of buying slaves in Africa was rising, reaching £25 in 1800. However, the price for selling slaves in the Americas had not risen as quickly and was only £35 in the same year. With the growth of trade to the Far East and India, Britain no longer needed the slave trade.
William Wilberforce made the abolition of slavery an issue for debate in Parliament. His ability as a speaker persuaded many others of the need to end the trade. James Stephen's bill of 1806 was also a key event.