> In 1807, United Kingdom prohibited slave trade in their colonies and pressed Portugal (that had very close relationship with UK) to do the same.

... and at the same time replaced them with "indentured labour", who just so happened to be poor Indians famished by savagery of the British taxes and the famines they unleashed, and had little choice or say in pretty much anything.

Kind of like how Indian-labour is now treated in Middle-East and elsewhere and the Indian-state exploits them for its own foreign policy.

Extraordinary tactic to kill your competition.