That's one of the criminal history of the British is that they routinely dumped as many criminals and convicts all over the world. They didn't want to deal with them. So the late 1700's and well into 1800's like your posts shows, they exported human chattel for almost a century.
All the convicts and prisoners and others were unpaid conscripts, human pawns to fight and eradicate any native populations so the british can colonize. It's kind of obvious looking at there documentaries and movies.