A person who alters evidence or gives a false account:the judge described him as a falsifier of history...
He was not a genuinely scrupulous historian but a falsifier and propagandist.
He is a falsifier, as any honest person who has studied history knows.
The findings of the inquiry were couched in virulent terms, accusing Graham of being a heretic, falsifier, person of irregular life, blasphemer, and excommunicate.