A. A. Milne published two original Pooh story collections: Winnie-the-Pooh and The House at Pooh Corner.
Winnie-the-Pooh appeared in 1926 and introduced the central cast, including Pooh, Christopher Robin, Piglet, Eeyore, Rabbit and Owl. The House at Pooh Corner followed in 1928 and expanded the world with characters and situations that became equally important to later adaptations, including Tigger’s introduction.
The total can be confusing because Pooh has appeared in many later books, compilations and licensed publications. Those works do not constitute additional original story collections written by Milne. Disney and other publishers have produced numerous adaptations and new adventures, but the two canonical prose collections by Milne are the foundation of the literary series.
Milne also wrote poetry about Christopher Robin and his toys. When We Were Very Young and Now We Are Six are poetry collections, not Pooh story collections, although they contain related material and helped establish the imaginative world surrounding Christopher Robin.