Snoopy started writing fiction on top of his doghouse on July 12, 1965. He always takes a typewriter, and puts it on his doghouse roof, then starts writing saying, "Here's the World Famous Author writing". How Snoopy fits his huge typewriter on top of his skinny doghouse roof, has never been revealed.
Snoopy starts many of his stories the same way, with the words, "It was a dark and stormy night." Lucy and Linus often reread Snoopy's work, and give him suggestions how to fix the story. Snoopy does not make very good use of their suggestions. For instance, in one strip Linus says Snoopy's stories all begin the same way, and tells the beagle he should change that. Snoopy responds by writing, "It was a stormy and dark night." In another strip, Lucy says Snoopy's stories would be improved by having more of a "once upon a time" beginning. Snoopy then writes, "Once upon a time it was a dark and stormy night".
On one Mother's Day strip, Charlie Brown recommends to Snoopy he write a letter to his mother so she knows he has not forgotten her. Snoopy writes "Dear Mom, I remember when I was born. It was a dark and stormy night." According to the TV special Snoopy's Reunion, Snoopy was actually right, as Snoopy and his siblings were indeed born on a dark and stormy night.
Snoopy often sends his stories off to be published. Initially he meets with success, but that quickly fades, and the publishers begin hating his stories, sending him an endless series of rejection slips. Sometimes, the rejection slips are very cruel and personal. For instance, one says, "We regret to tell you that your story does not suit our present need. On second thought............ Actually we don't regret it at all." Another says "After reading your last story we just have one question. What did we ever do to hurt you?" In the strip from June 18, 1974 , it is revealed that Snoopy has enough rejection slips for Woodstock to make a quilt out of them. Snoopy eventually manages to get a story published once again, in the strip from October 27, 1995 . However, nobody buys a copy of his novel.
In a series of strips from February and March 1972, Snoopy decides to write the biography of Helen Sweetstory, the author of the Bunny Wunny series of children's books. The beagle sets off to find Miss Sweetstory's house and, having apparently found it, returns home and starts writing the story of her life. Charlie Brown finds the biography that Snoopy is writing frustratingly lacking in detail, which Snoopy excuses by stating he is respecting Miss Sweetstory's privacy. In the March 3, 1972 strip, Helen Sweetstory says in a newspaper interview that she has not given anyone permission to write her life story. When Charlie Brown reads this to Snoopy, the beagle immediately abandons writing the biography and starts playing at being the World War I Flying Ace instead.