What happens to dead bodies, the subtitle of this book asks. Well, I "dug up" a fascinating anecdote in this intriguing book that provides an answer for one dead body that went to war.
Death to Dust: What Happens to Dead Bodies?, by Kenneth V. Iverson, M.D. (Galen Press, Tucson, 1994) is the book. Despite it grisly title (and there are some squeamish chapters), it is packed full of literary and historical references about death that are quite interesting.
The most fascinating incident I came across in a random sampling of contents concerns a dead body used as a decoy in World War II and the key role it played in the war's outcome.
As the Allies planned an assault on Sicily, they schemed to deceive the Germans that they intended to land elsewhere. Cutting to the chase and an ingenious plan... the cadaver of an anonymous pneumonia victim was dressed as a Royal Marine and provided with phony papers about plans to invade areas east and west of Sicily. The corpse was strategically placed in the sea, in a simulated drowning, to where it would wash up along a part of the Spanish coast into the hands of German spies in the area.
Operation Mincemeat, as the plan was called, worked beautifully. The Germans took the bait hook, line, and sinker (if that's not too distasteful an analogy). They moved a significant number of troops to the suspected area of attack and the Allied invasion of Sicily ensued successfully against a much reduced defensive force. Mincemeat had the further benefit of causing the Germans to disregard later discoveries of genuine documents uncovered a few days after the D-Day invasion and later the drive into the Netherlands. In each case, critical information recovered was disregarded as another ruse by the Allies.
A more detailed account of Operation Mincemeat can be found here or in The Man Who Never Was, by Ewan Montagu--a 1954 book about the operation.