Dr. Harry Norman Turtledove is an author. He is best known as a writer of alternate history, historical fiction, fantasy, science fiction, and mystery fiction.In addition to his birth name, Turtledove writes under a number of pen names: Eric Iverson, H. N. Turteltaub, Dan Chernenko, and Mark Gordian. His first book, "Wereblood," was published in 1979, and he has since published over 50 novels.Turtledove received his Ph.D. in Byzantine History.