This book is the first comprehensive listing of these ships in English and covers the development of all the naval vessels owned or deployed by Spain during the period of the Bourbon monarchy from 1700 to 1860 (including the period of French control during the Napoleonic Wars), but it also sets the scene for that period by summarizing the origins of Spanish naval development under the preceding Habsburg regime.

The main chapters list all the naval vessels from 1700 onwards (including those 16th century ships which survived into the new regime in 1700) by type, with the first chapters listing the ships of the line (navíos in Spanish terminology) and frigates in descending order of firepower, and subsequent chapters covering minor and ancillary vessels. Where available, a brief service history of each individual ship is given. A comprehensive introductory section includes a group of background essays designed to provide the reader with a deep understanding of how Spanish naval forces operated, and the context within which they were organized.