When did England abolish slavery and how did this come about?

Fredrick Douglass had to flee the country a couple times, and he seemed to be deeply welcome in England. I know that at one point in history, England also had slaves. Did Douglass have any impact on the British empire freeing their slaves?

Pictured above is one of the several meetings between English abolitionists and their adversaries in Parliament. A man by the name of William Wilberforce had been working to abolish slavery since 1798. England ended the slave trade in 1816, and freed all the slaves in the empire by 1833. So, England had freed their slaves before Frederick Douglass had even arrived in London. Wilberforce had been very influential in Parliament by arguing Christian viewpoints, and he also had many stories of the horrors of the slave trade from John Newton, an ex-slave trader. (http://www.britannia.com/bios/wilberforce.html)

I'd like to say that the fight for an end to slavery had been going on for a long time. Recorded slavery had been around for over four thousand years, with the Egyptians enslaving the Jews. The first group of people to actually speak out against the trade were the Quakers around the year 1787. So, Wilberforce is to be given a lot of credit for the destruction of the trade. Of course, Frederick Douglass actually asked the British to be the leading effort in showing the world the injustice of slavery. War was necessary to end the trade in the U.S., as we all know. Had it not been for Wilberforce, however, the abolitionist would not have included such a large number of supporters.There is a very good and inspirational movie on the matter. Check it out sometime. (http://www.victorianweb.org/history/antislavery.html, http://www.yale.edu/glc/archive/1084.htm)