Military drones have recently been hailed as a revolutionary new technology that will forever change the conduct of war. And yet the United States and other countries have been deploying such unmanned military systems for more than a century. Written by a renowned authority in the field, this book documents the forgotten legacy of these pioneering efforts, offering the first comprehensive historical and technical accounting of unmanned air, land, sea, and underwater systems. Focusing on examples introduced during the two world wars, H. R. Everett meticulously traces their development from the mid-nineteenth century to the early Cold War. A pioneering Navy roboticist, Everett not only describes these systems in detail but also reverse-engineers the designs in order to explain how they operated in real-world conditions of the time. More than 500 illustrations -- photographs, drawings, and plans, many of them never before published -- accompany the text.Everett covers the evolution of early wire-guided submersibles, tracing the development of power, propulsion, communication, and control; radio-controlled surface craft, deployed by both Germany and Great Britain in World War I; radio-controlled submersibles; radio-controlled aircraft, including the TDR-1 assault drone project in World War II -- which laid the groundwork for subsequent highly classified drone programs; and radio-controlled ground vehicles, including the Wehrmacht's Goliath and Borgwald demolition carriers.