Assuming that the Slavery Abolition Act 1833 goes through like it did OTL, how would the Slave owners and Slaves react to this?
I think this is a big assumption. For one thing, as Rodest Revolution points out, this will mean that millions of more slaves will have to be paid for as compensation, and for another thing, this scenario means that the Caribbean and American planter lobbies will be united. OTL the Caribbean planters were able to delay actual abolition till 1838. With the South presumably supplying even more cotton to the UK in this TL, and the compensation issue, I wonder just how long the planters would be able to drag it out.
Also unlike the Caribbean colonies, colonies in the OTL US would have the possibility of armed revolt if Britain tries to abolish slavery, so it's possible there could be some sort of weird American Civil War analogy. Although since in this case the South's main market would be against them, they might not dare. A lot might depend on British-French relations, too. If the northern colonies have any grievances with the British government at the same time, it could really turn into a mess.
I would also expect abolition to have proceeded more slowly in the northern colonies in this TL, but it would be such a small player in their economies that I wouldn't expect it to be any impetus for revolt like it would in the Deep South, and by 1833 I think most of the OTL states that abolished slavery would also have abolished it in this timeline, so maybe not too many differences there.
But really, at the end of the day, I think this entire scenario is unrealistic. I think even with a victory in the ARW it is highly unlikely that Britain can maintain enough control over their North American mainland colonies by the 1830s to retain the power to abolish slavery there. By 1830 the OTL US had a population as large as England's; something would have to give. Personally I think the most likely scenario is that there's a second revolution, but the alternative is that Britain grants the ATL US sweeping autonomy sometime in the next few decades after the failed ARW. The alternative to that is almost certainly a second revolt, and I think a second revolt would be the most likely outcome anyway. The best outcome as far as slavery goes would be for that second revolt to go in a radical direction like the French Revolution and have slavery abolished during the war. Though if that happened I don't know if the Deep South would join in; a Second American Revolution ATL US might end up split.
I agree, Sloreck. I suspect abolition would have happened before 1840. Many people don't realize that American slavery deteriorated for a long time before experiencing a second wind in the mid-19th century. It was rejuvenated by a combination of factors: technological advancements, territorial expansion, and the protection of a belligerent, expansionist U.S. government dominated by southerners for half a century. If the revolution were to have failed, none of this would have happened. The cotton belt would not even have been settled. If the British could abolish slavery where it was most lucrative (in the Caribbean sugar plantations), they could certainly have abolished it where it was moribund and regarded with moral ambivalence even by its hereditary practitioners.
I don't agree with this assessment, because I don't buy the argument that plantation slavery was in any sort of decline post-1800. There had been a major cotton bust right around 1825, but that was just a fluctuation; it had been at record highs the 5 years prior to that, and cotton was no less profitable at the start of the 19th century than it was during the middle of it. The price of slaves during that same period 1800-1830 also held steady or rose, meaning that slavery was still a profitable institution or even an increasingly profitable institution. OTL the vast majority of slaves in 1830 were in the Cotton Belt east of the Mississippi, and why would a British victory in the ARW have resulted in the cotton belt not being settled? It was the most profitable single part of the country.
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