The Encyclopedia of Warfare is a comprehensive hardcover reference work published by Amber Books, with a foreword and editorial contribution by Professor Dennis E. Showalter, a military historian and former president of the American Society for Military History. The set comes presented in an elegant slipcase, making it an ideal gift or collector's edition.

Spanning almost five millennia of human conflict, this 1,088-page volume contains more than 5,000 entries arranged chronologically, covering wars, campaigns, empires, rebellions, and counter-insurgencies from the ancient world through to modern conflicts including Ukraine. Topics range from raids, invasions, and sieges to trench warfare, naval battles, aerial dogfights, civil wars, guerrilla campaigns, and nuclear strategy. Each war narrative includes descriptions of associated campaigns, battles, and sieges where applicable, and all content is accessible via an extensive index.

The volume features over 610 maps created specifically for this edition, along with two plate sections containing 100 photographs. With approximately 350,000 words, the text is written to be accessible to both students and general enthusiasts while reflecting current thinking among professional military historians. The updated edition (ISBN: 9781838866372) includes two 32-page photographic plate sections housed in a slipcase.