In the novel, Uncas, son of Chingachgook dies in a doomed attempt to save Cora (rather than the blond Alice) as represented in the movie.
Actually, I thought the James Fenimore Cooper novel was an excellent classic, considering it was written in 1826 and one has to suffer through the period dialogue. But the story is well constructed and the characters are developed with depth. One of the major characters in the book that only receives passing notice in the movie is that of the aged Sagamore Tamenund ... a legendary chief of the Delawares. But even more interesting and important to the controversial nature of the book, for it's time, is the character Cora, eldest daughter of British Colonel Munro. Cora Munro is the first African-American heroine in American literature. To see how Cooper presents this situation our first encounter with Cora is in the first chapter, when Cooper describes her:
"The tresses of this lady were shining and black, like the plumage of the raven. Her complexion was not brown, but it rather appeared charged with the colour of the rich blood, that seemed ready to burst its bounds. And yet there was neither coarseness, nor want of shadowing, in a countenance that was exquisitely regular and dignified, and surpassingly beautiful"... We find that she is the product of Munro and his first wife, a mulatto when he was stationed in the West Indies. His first wife dies and he returns to Scotland to marry his first love who becomes the mother of Alice, half sister to Cora.
At any rate, Uncas, Cora and Magua all die in a final battle scene of Chapter 32... Hawkeye (Natty Bumpo, La Longue Caribine, Deersalyer, all names of the main character) and Chingachgook's friendship is even more cemented, and at the end they wander off together. A very good read...