This book tells a history of Ireland through the examination of 100 key words from the Royal Irish Academy's Dictionary of the Irish Language, the most comprehensive dictionary of Irish in existence. The book is aimed at a popular audience and is intended to increase awareness and understanding of the Irish language for the period spanning the seventh to the seventeenth century, but it assumes no prior knowledge of the language on the part of the reader. It is divided into themes, including writing and literature, food and feasting, technology and science, the body, and other worlds, and each entry will explore a word or group of words related to a particular idea or object, such as 'home', 'death', 'people' or 'book'.

Entries are short, c. 500 words, and self-contained, so that readers can dip into the book where they please.