Based upon exhaustive research in numerous archival sources, including the personal papers of the major British military and political leaders of the day, this is a comprehensive study of British military planning during a period in which long-successful defense and military strategies had to be reappraised in light of new technological advances. As Michael Partridge notes, Britain emerged victorious in 1814 after twenty-two years of war with revolutionary and Napoleonic France; however various technical and international developments--particularly the invention of the steam engine--gravely undermined Britain's security between 1814 and 1870. Because steam power enabled ships to maneuver independently of wind and tide, Britain was now vulnerable to attack from all sides, forcing her to devise new defensive strategies to repel invasion. Partridge thoroughly examines Britain's response to the advent of steam power as well as the special military defense problems faced by the country as a result of its geographical position and contemporary political realities. Following a brief introduction, Partridge offers an overview of Britain's strategic position in the years following the war with France. Subsequent chapters examine each aspect of the country's military planning in detail, beginning with an exploration of the decline of the Royal Navy--at one time the unchallenged mistress of the seas and far larger than any rival's naval force. Partridge then addresses the internal machinery of defense planning, the political constraints placed upon defense planners, the effects of popular aversion to a standing army, and the new awareness of Britain's strategic vulnerability. Individual chapters are devoted to the three major prongs of Britain's land defenses: the regular army, fortifications, and the militia, yeomanry, and volunteers. A bibliography is included for those who wish to pursue further research in this area. Indispensable for students of military history, this study offers important new insights into Britain's ability to adapt to the new military and technological realities of the early Nineteenth-Century.