"In 1833, Britain used £20 million, 40 per cent of its national budget, to buy freedom for all slaves in the Empire. The amount of money borrowed for the Slavery Abolition Act was so large that it wasn't paid off until 2015. Which means that living British citizens helped pay to end the slave trade.
And even after all that, some years later they started practicing Indentured Servitude, which was basically Slavery of the Poor.
Rented slaves