How is The Last of the Mohicans an unrealistic historical novel?

In Harry E. Shaw's The Forms of Historical Fiction: Sir Walter Scott and His Successors, (Ithaca: Cornell University Press, 1983), he states that Scott "captured the immense power and spirit of historical Scotland and dramatized it so well that the people and places came to life."

The sub-genre of historical fiction uses real historical events or real people and dramatizes the life and times in which the author is writing. No one did it better than Walter Scott in his novel Ivanhoe. 

In The Last of the Mohicans, Cooper used an immense amount of detail to depict the world as it was in 1775, though in real life, the Indians were Mohegans and not Mohicans, and many of the fictional characters did not exist. But it does not detract from the ways in which life existed back then and gives you some idea of not only what life was like, but also an idea of a real event surrounding the death of Jean McCrea in 1777 at the hands of Algonquin Indians.