Caste is hierarchically graded, each caste being graded inferior to those above it and superior to those below it. The status of man is determined by the rank of that caste in the hierarchy. Once born in that case, his status stands pre-determined and immutable irrespective of any talent he may show or wealth he might accumulate.
They should interview other people who fought in that same war ( which would be back up witness for these two different accounts). So whoever has the most back up witnesses must be telling the truth ( also make sure the other people you interview don't know they are back up witness).
The law authorized the president to negotiate with southern Native American tribes for their removal to federal territory west of the Mississippi River in exchange for white settlement of their ancestral lands.