Superman: Last Son of Krypton
Superman: Last Son of Krypton is a novel written by Elliot S. Maggin and based on the DC Comics character Superman. It was published in 1978. The novel was published as a tie-in to the release of Superman: The Movie, with an image of Christopher Reeve on the cover and (in its original edition) a section of photographs from the film. The novel is not, however, a novelization of the film, and in fact diverges from the film story.

Plot summary
Last Son of Krypton is Elliot S. Maggin's first Superman novel. It tells the "life story" of Superman; from his birth on the planet Krypton, to his childhood in Smallville and his career as Superboy, to his arrival in Metropolis and his career as Superman. The main antagonist in this story is a mysterious alien ruler with ties to Superman's past. Superman and his greatest enemy Lex Luthor must join forces to retrieve a document written by Albert Einstein and stop the alien ruler.

History 
Excerpts from a 1996 amazon.com interview of the author, Elliot S. Maggin  (original removed from Amazon.com)

"Last Son of Krypton started out as a treatment for a movie -- the Superman movie that I was trying to convince DC Comics needed to be made as far back as 1974. When Mario Puzo showed up at the office one day to tell me he'd gotten an assignment to write a Superman movie and would I spend a couple of days with him telling him who the character was, I was thrilled and disappointed. I spent two days with Puzo, telling stories and smoking enormous cigars, and had a fine time. Then I took my ignored little film treatment upstairs to Warner Books where a senior editor said go ahead and write a novel out of it. I did, and through a series of unlikely events, the novel was published the same day as the movie was released, and became a bestseller."

"The book was released when I lived in New Hampshire, the day Superman: The Movie  was released.  I got a frantic phone call that week from the guy who was president of DC Comics saying that Alexander Salkind -- the producer of the movie -- wanted to sue me. Apparently someone had finally read him the book or something, and he thought there were too many incidents in common with the movie. I said that I had not seen the movie or read the script, but that I had handed in my manuscript a full year before Mario Puzo handed in his script, and owing to my conversations with Puzo. I told this guy where to look for proof of that, and said maybe I should sue Salkind."