How could colonies help them other countries militarily

Prior to the presence of europeans on the continent, the slave trade in africa a) did not exist in any form. b) was limited to internal trade only. c) included the trans-saharan and indian ocean slave trade. d) was rarely needed due to the lack of an agricultural economy.

To keep other european powers from threatening its empire in america, spain sent soldiers, settlers, and?

Why did french and austrian troops stops revolts in spain and italy