One of the comforting stories the British told themselves in the 19th and 20th centuries was that they were implacably opposed to slavery. Britons had decided “that the disgrace of slavery should not be suffered to remain part of our national system”, or so Lord Stanley, the colonial secretary at the moment of abolition, maintained. It was a claim willingly accepted by later generations. The 1833 Act that abolished slavery in Britain’s Atlantic empire reflected the undivided national will. But recent scholarship casts doubt on that verdict. The West Indian planters, who held hundreds of thousands in bondage, were well-connected and influential. The freeing of their captive workers did not seem to them inevitable. Many abolitionists thought the same, despairing at the entrenched power of the slave masters. When slavery went, it went because a series of political crises in Britain splintered the pro-slavery Tory coalition that had dominated politics for decades. It ended too because resistance by the enslaved in the Caribbean convinced legislators in London that slavery was no longer sustainable. But not …