Anative american movement in the 1890s that believed a ritualistic ceremony would result in the reanimation of indian dead and the defeat of the white invaders into the west.

spread of christianity

i believe it would influence their own way of understanding things. it shall be a foundation where they can draw or start an argument.   historians are also  scientists that  have their tools of analysis and expertise to unlock a variety of difficulties such as relationships of man, origin, politics, economy, and culture. based on facts and understanding on these areas, they may shade light to extract ideas and develop options to validate a hypothesis or debunk it.

you really can't answer this on your own?

it required the unanimous approval of the states before the congress could enact any measure.