The Slave Trade Act of 1807 ended slave trading, in terms of people going to Africa and kidnapping people, and hauling them across the ocean like cargo. But the existence of slavery, as in owning, working, and breeding slaves was allowed until the end of the Civil War. Why did the overseas trade end, but the practice was allowed until 1865?
Slavery was an economic practise in the American South. Slaves were property, a capital investment in applied Labour. It was a means to an end, the way to cultivate the cash crops of Tobacco, Cotton, and in the coastal piedmont region of the Carolinas, Rice. It seemed only practicable as the African Races seemed less suceptible to the diseases of this torid zone. It was said, also, Slavery was Divinely sanctioned. Since the institution of Slavery was mentioned in the Bible, it was said the Children of Ham were to be subserviate to their betters. (That any African is less deserving or capable than any European is another debate, and I hope we can avoid such a silly debate). Certain European nations (first Danmarck, then Britain) outlawed slavery and forbid the trafficking in human flesh. Not to incur an international war, the US Congress also forbade the external trafficking in slaves, but allowed internal trafficking. The effect of this was to drive the price of prime field-hand slaves. As for the debate over Slavery, pro or con, much ink on the topic has been spilt. I am not about to write this debate again, but I can recommend a good title for you if you are interested in a scholarly answer.
In short.....Don't know. Like 6 replied, there are a lot of reasons why it stayed around for so long but there is no one single answer to your question. There were however a lot of occasions when black Americans served in the military as far back as the revolutionary war and strangely enough the civil war.( on both sides, even though the southern black soldiers were mostly slaves hoping to get their freedom by serving) Capt. B. Pinchback, as an example, was in the Union Army in the Civil War and also the 1st black (half black) governor in the U.S. In Dec. of 1872 he was the governor of La. for about 6 weeks while the governor was under impeachment proceedings. He was also later voted to both houses of congress but was not seated because the democratic majority had a few problems with his race. Go figure.
Prime, now that I have pondered your question for a while I am going to attack it again, perhaps from a new perspective. The Slave Trade Act of 1807 did not stop tradeing in human flesh. It applied only to the importation of slaves from Africa, and that was sort of a moot point as Britain declared they would inteasrdict international trafficking. And as I wrote already legal slavery persisted in the US until the 1860s. What I did not mention is that Slavery persists to this day in one form or another. There is an argument that in the US stagnant wages over the past three decades while all economic benefit having gone to the top 10%, and weighted to the top ,01%, has meant de facto "wage slavery". There was a made-for-TV movie which I believe was shown on PBS called "Slavery by Another Name". It explored how in the American South African-American men have been arrested on bogus charges and enprisoned for long sentances merely was a legal ploy to place them in bondage so as to use their bodies as LABOUR, as de facto Slaves.
I have also heard about the supposed "legal slaves" in jail. Please answer me this, why just black people? Why could there not also be people forced into servitude as whites or Latino? As we are being romantic about modern slavery, we could really call anyone who is chained to a desk or factory work, or captive by a family business over multi-generations, slaves. They cannot quit without repercussions. They cannot leave. They don't have choices.
