Embalming
Embalming became more common in the United States during the Civil War, as a service provided by a new profession of “embalmers” who could assist in body retrieval given that fallen soldiers were far away from their relatives.
After the war, the embalmers continued offering their services as a persisted part of post-mortem activities.
More on embalming (and death in general) can be found in this Freakonomics episode with Caitlin Doughty.