Why are turning points important on the process of periodization

How and why did the policies of the federal and state governments toward native american people change between 1790 and the 1850s. what were the reaction of native american people to these policies?

The roosevelt corollary specifically states that the united states would play what role in latin america? a. mediator c. police power b. watchdog d. buffer state

Who was the governor of the spanish territory of louisiana who offered financial assistance as well as military supplies to the patriot cause?