Where the Wild Things is the most important picture book in history. It changed everything. In sports terms, it’s the equivalent of Wayne Gretzky turning pro; all of a sudden, hockey was played differently: Goal scorers scored goals differently, the defense defended differently, and goalies minder their nets differently.
That’s what Wild Things did. Before its publication children’s books were pretty, and the kids in them were well-behaved. Sendak gave creators permission to acknowledge that kids sometimes behaved badly, and that’s okay. He darkened the acceptable palette.
Pictures books today would not be the same without Where the Wild Things Are.