Battlefield evacuation

Battlefield evacuation is the movement of wounded and sick soldiers from the point of injury to medical care, and onward to hospitals farther back. It covers who carries them, by what means, through which stages, and how long each stage takes.

For most of history there was no system. The wounded walked, were carried by comrades, or lay on the field until the fighting ended. Many died there of bleeding, cold or thirst.

Organised evacuation is largely modern. In the 1790s Dominique-Jean Larrey, a French army surgeon, introduced light horse-drawn ambulances volantes, flying ambulances, to collect the wounded during a battle rather than after it. In 1862 Jonathan Letterman, medical director of the Union Army of the Potomac, set up a dedicated ambulance corps and a chain of dressing stations and field hospitals. Twentieth-century armies added motor ambulances, hospital trains and ships, and, from the Korean War, helicopters.

By the First World War, the British Army moved a wounded soldier through a series of stages:

1. Stretcher-bearers carried him from where he fell to a regimental aid post for first dressing.
2. Bearers or ambulances took him back to an advanced dressing station.
3. Motor ambulances carried him to a casualty clearing station, where surgery could be done.
4. Ambulance trains or barges took him to a base hospital, and hospital ships to Britain if needed.

Each stage sorted the wounded and passed them on. Other armies used similar chains under different names.

• Vindonissa, about AD 35. The Roman army had medical staff and buildings interpreted as hospitals, but how an injured soldier was moved to them is not established. The Hands That Survived Rome does not show a stretcher-and-ambulance chain, because none is documented for that time and place.