A comment on this post  suggests that slavery is, or was, somehow essential to capitalist development. This notion confuses historical happenstance with fundamentals. (Please, please do not cavil that my use of the term “historical happenstance” perhaps signals some secret indifference on my part to slavery. There’s no question that slavery is an utterly heinous institution, justifiable under no circumstances.)
Slavery and capitalism are opposites.
The fact is that slavery disappeared only as industrial capitalism emerged. And it disappeared first where industrial capitalism appeared first: Great Britain. This was no coincidence. Slavery was destroyed by capitalism.