Why did spanish plantation owners in the west indies begin using enslaved africans instead of enslaved natives?

Because most of the enslaved natives died of disease, just like the natives who weren't enslaved. At the same time, there was an economic collapse in West Africa, leading to an almost unlimited availability of cheap slaves.They had all died off due to European diseases.They were defined by the Queen of Span as her subjects, the Africans were not.

the answer is )multiethnic

president thomas jefferson hoped that the embargo act of 1807 would the united states by demonstrating to britain and france their dependence on american goods, convincing them to respect american neutrality and stop impressing american seamen. instead, the act had a devastating effect on american trade.