Lieutenant Colonel Arthur "Art" Alphin is a retired United States Army officer and military historian.
He is the founder and owner of A-Square, manufacturer of American hunting rifles. He taught military history at West Point. Since retiring he has co-authored several books with his wife and children's author Elaine Marie Alphin.
He also assisted ghostwriter Lisa Harkrader in writing Animorphs #51: The Absolute, by providing her with information about tanks and reading over the book to check for errors.