The teddy bear that Christopher Robin Milne received for his first birthday did not start out with the name of Winnie the Pooh. Pooh originally belonged to a swan, as can be seen in a poem from When We Were Very Young. And Winnie originally came from a bear at the London Zoo that Christopher Robin used to play with. In Winnie-the-Pooh, A. A. Milne wrote that the name, Winnie, was based on a polar bear. Whether a slip of the pen, or just a memory lapse, that bear at the zoo was not a polar bear, but an American black bear.
Winnie was brought to England in 1914 by an army officer named Harry Colebourn. Colebourn had been trained at the Ontario Veterinary College and was attached with the 34th Regiment of Cavalry. On his way to join the 2nd Canadian Infantry Brigade and to embark to England for the war, his train stopped at White River, Ontario. There, Lt. Colebourn bought a small female black bear cub from a hunter who had killed its mother. Colebourn named the bear Winnie, after his hometown of Winnipeg. The bear became a mascot for the Brigade and followed the soldiers throughout their camp on the Salisbury Plain.
When the Brigade was called to action in France, Lt. Colebourn took Winnie to the London Zoo for a long loan. Colebourn survived the war and formally presented the London Zoo with Winnie in December 1919. Winnie became a popular attraction and lived until 1934.
The bear was Christopher Robin's favorite at the zoo, and he often spent time inside the cage with it.
So when Christopher Robin goes to the Zoo, he goes to where the Polar Bears are, and he whispers something to the third keeper from the left, and doors are unlocked, and we wander through dark passages and up steep stairs, until at last we come to the special cage, and the cage is opened, and out trots something brown and furry, and with a happy cry of "Oh, Bear!" Christopher Robin rushes into its arms. Now this bear's name is Winnie, which shows what a good name for bears it is, but the funny thing is that we can't remember whether Winnie is called after Pooh, or Pooh after Winnie. We did know once, but we have forgotten....
--Taken From "The Page at Pooh Corner"