Does Sula tell American history

Yes

Sula is a novel that was written by Toni Morrison. It is about the struggles of African Americans in the first half of the 1900s. The struggles described are those based upon racism-injustice and non-equality. The struggles detailed are those of perseverance in the face of resistance, resistance brought about by those who sought to keep African Americans down (socially and economically). Thus, yes, because African Americans are Americans, and this novel details the truth of their struggles, Sula is definitely a novel that tells American history.