Since we were first introduced to Harry Potter more than 20 years ago, his Wizarding World has expanded far beyond the sprawling grounds of Hogwarts and cobblestone streets of Diagon Alley.

Rowling has said the least about llvermorny, the North American school, thus far, but she did offer backstories on the other three schools. Castelobruxo is, appropriately, a castle tucked into the ...