What steps do historians make before writting about their findings

on april 6, 1917, the u.s. joined its allies--britain, france, and russia--to fight in world war i. under the command of major general john j. pershing, more than 2 million u.s. soldiers fought on battlefields in france.

after the aryan's settled in india they changed for the better i bellieve they changed from nomads having to keep moving to being farmers   they were aswell avaible to turn the ganges river into farmland.   which is great they added a big affect on farming as we know of it today.