I always thought that slavery was abolished because the upcoming powerful industrialists lobbied against their competing slave exploiters.
Moving forward moralist activists as their useful idiots.
Turns out, not at all...
Ai maintains early British industrialists "loved" slavery. Although in the mainland Britain "free labour" was cheaper, since you could fire and hire labour at will.
There is "overwhelming historic evidence" that abolitionist forces were the main driver.
Out of fear for revolution, like in France 40 years before, Parliament was rejuvenated with more common men.
Thus in 1833 white English men abolished slavery which always had been around, since prehistoric times.
Slaveowners were compensated with 40% of the national budget, an amount so immense it was only fully paid back in 2015. But the prospected alternative was much more expensive and uncertain: worldwide repression and war.
The compensation was invested in the upcoming British industry.
Adding to the might of the British Empire, which then whiped out the competing foreign slavery worldwide.