Although animals were sometimes featured in children's literature prior to the 19th century, the popularity of animal characters surged after the industrial revolution in Britain and Europe. This is mostly attributed to the changing views of animals in society and their changing status from "pests" to "pets." Prior to the industrial revolution, animals were often seen as carriers of disease and were kept away from children. The 19th century, however, began to see a more sentimental, protective attitude towards animals, bringing them into the forefront of popular children's literature.
One of the reasons for humanizing animals in children's literature is inclusivity. By creating characters that are not human, the author allows the child to relate to the character while avoiding issues of gender, race and class. A bird or a bear in a children's story is a neutral, recognizable character that a child of any race, gender or socioeconomic status is able to relate to on a deeper level.
Another reason for the use of animals in children's literature is the author's ability to give them freedoms and abilities not given to humans. Free of the adult responsibilities of everyday life, animals are able to navigate the story's fictional landscape and experience the world around them with the same carefree attitude of children. This makes the characters easier to relate to and their adventures more fantastical and thus stimulating for the imagination.
Recent debate among literary scholars has raised the question of idealization in the fictional animal world created by children's literature. Some argue that by presenting children with an idealized animal world in which there is no violence, killing or conflict we are sheltering children from the harsh realities of life. When they are eventually exposed to violence in the real world, they are more likely to attempt to rationalize it and ideologize it, as the moral lessons taught to them by the animal characters in children's literature have not prepared them for dealing with such issues.