This reference work investigates the vast and complex landscape of Celtic mythology, seeking to provide a comprehensive catalog of its figures, themes, and cultural origins. James MacKillop, a scholar of Celtic studies, compiles an extensive array of entries that bridge the gap between ancient pagan traditions and the evolution of folklore into the modern era. The book utilizes a structured lexicographical framework to organize disparate sagas, legends, and historical concepts into an accessible format for researchers and enthusiasts alike.

Experts and scholars frequently cite this volume as a foundational reference tool for those exploring the intricacies of Celtic tradition. Readers often note the clarity of the entries, which manage to distill dense mythological material into concise, informative summaries suitable for both academic and general inquiry.