With cyberwarfare and shrinking drones dominating recent headlines, it can often seem as if the nature of combat is changing faster than ever. But in Foreign Policy's War Issue, Thomas Barnett examines these transformations and reminds us that combat roles have been evolving ever since the Civil War, when the primary role of marines was to act as snipers hidden away in the masts of ships.
As combat roles have changed, so have the military's recruitment efforts. From the imploring "cash prize" Civil War-era flyers to the sometimes-clumsy attempts to entice women and minorities into the service, these images give us insight into not only who served but what service meant at the time.
Above, a Civil War poster advertises Navy service as an attractive alternative to the wartime military draft.