Trolls are everywhere. They lurk on the internet; they fill the pages of popular fantasy literature; they are hunted in Norwegian film. They are the homeless in California; they are comforting or threatening characters in children's books; they are amusing dolls. Although trolls are ubiquitous today, for centuries they were confined to the landscape of Scandinavia. This book is a history of trolls from their first appearances in folk tales - some people reported actual encounters with trolls, and others found such encounters plausible even if they were not sure - and follows a natural transition from folklore to trolls in other domains of popular culture. Indeed, trolls would not be interesting had they not made this jump, first to illustrations in the Nordic book market, then on to Scandinavian literature and drama, and far beyond. Since then they have never gone away, and in their various guises they continue to appeal to the imagination around the world. From the Vikings to the Moomins, the Brothers Grimm and the Three Billy Goats Gruff, this book explores the panoply of trolls and their history and their continuing presence today.