Early nineteenth-century demographic trends on sugar estates in Jamaica, the most important British Caribbean colony, are examined through the 1817-32 public slave registers. We seek evidence regarding the background to the island's 1831-2 popular insurrection, the immediate cause of the London parliament's vote in 1833 to abolish colonial slavery. Some historians argue that the revolt occurred as 'political' effect from a sudden upsurge of metropolitan anti-slavery activism in 1830-1. They believe the uprising broke out despite improvement in enslaved people's material welfare, favoured by many slaveholders to secure population increase after the closure of the British transatlantic slave trade in 1808. Alternative 'economic' assessments judge that increasing workloads had been aggravating popular unrest before the revolt. Commercial pressures, and the imminent likelihood of emancipation, allegedly outweighed welfare concerns. The excess of slave deaths over births widened between 1817 and 1832. However, the registers show that demographic deficits resulted mainly from the ageing of the last Africa-born cohorts. Jamaica-born enslaved people became self-reproducing. There was no general pre-1831 regime deterioration. Most slaveholders sought to maintain their Jamaican assets for the long term through pro-natalist measures, and did not expect emancipation. The revolt's causes were thus more 'political' than 'economic'.