The Hawthorn Realm was one of the five royal houses of black squirrels. They were very secretive, and closed their borders to outsiders hundreds of years ago. Their queen used magic and was said to cast spells with a hawthorn branch. She wore a gold hawthorn blossom around her neck.

When Morella and Modequai arrived in Greenwich Park, it was rumoured that they were the last survivors of the Hawthorn Realm.