The Battle of Shiloh was a major Civil War battle that occurred on April 6 and 7 of 1862 in Hardin County, Tennessee.

The battle occurred when 40,000 Confederate soldiers led by General Albert Sidney Johnston clashed with a line of Union soldiers occupying ground near Pittsburg Landing on the Tennessee River.

The Confederates drove the Union troops from their camps and slowly surrounded, captured, killed or wounded most of them. The following day, a large number of Union reinforcements arrived and completely overwhelmed the weakened Confederate troops, forcing them to flee the battlefield.

After the battle took place, over 16,000 wounded soldiers lay in the rain and cold mud for over two days as overwhelmed doctors and nurses struggled to locate and treat the soldiers.

Some of these wounded soldiers later reported that as they lay on the ground awaiting help, their wounds started to glow in the dark, according to the book The Aftermath of Battle: The Burial of the Civil War Dead:

“Many soldiers were forced to lie in the mud and muck for two days while waiting for the medics to get to them. When the sun went down, an eerie blue-green glow began to be seen in several areas of the darkened Tennessee battlefield. Strangely, the wounds of some of the stranded soldiers were emitting this glow. No one had any idea what this phenomenon might portend, but the doctors and nurses noticed that those whose wounds had glowed brightly in the dark had a significantly higher survival rate than those whose wounds were not illuminated. Additionally, the wounds healed at a faster rate, and more cleanly. Because of the seemingly magical properties, the coloration became known as ‘Angel’s Glow.'”

At the time, the reason for the glow was a mystery but doctors did note that the wounds that glowed healed faster than those that didn’t. The mystery remained unsolved until 2001, when two teenagers finally uncovered the source of the glow.

After the two teens, Billy Martin and John Curtis from Maryland, conducted a variety of scientific experiments, they discovered that the wounded soldiers became hypothermic as they lay in the mud.

This lower body temperature allowed for the growth of a bioluminescent bacterium called Photorhabadus luminescens, which inhibits pathogens, to develop in the wound.

This bacterium not only caused the wounds to glow but also prevented them from became gangrenous, which saved the lives and limbs of many soldiers.

Although it was common for wounded soldiers to lay on the battlefield for days after the battle’s end, glowing wounds were not a widespread phenomenon of the Civil War.

The glowing wounds of the Battle of Shiloh are mostly due to the wet, cold and muddy conditions of that April battle as well as the fact that this glowing bacterium is known to attach itself to a certain type of flatworm, called planaria, which is commonly found in the Shiloh area.

Since worms only come to the surface when it is wet, there was an abundance of the worms moving throughout the mud during and after the rainy battle.

The discovery won Martin and Curtis the top prize at the Siemens International Science Fair Competition. Curtis later went on to pursue a career in science and Martin pursued a degree in American history, specializing in the American Civil War.

Sources:

The Aftermath of Battle: The Burial of the Civil War Dead by Meg Groeling

Los Angeles Times; Glowing Wounds and the Civil War; Rosie Mestel; July 2 2001: articles.latimes.com/2001/jul/02/health/he-17705

Helping Boys Succeed in School: a Practical Guide for Parents and Teachers; Terry W. Neu, Rich Weinfeld;

Science Netlinks: Glowing Wounds: sciencenetlinks.com/science-news/science-updates/glowing-wounds/

Smithsonian Magazine; Civil War: 8 Strange and Obscure Facts You Didn’t Know; November 15 2010: blogs.smithsonianmag.com/history/2011/11/the-civil-war-8-strange-and-obscure-facts-you-didnt-know/

Civil War Trust: Battle of Shiloh: civilwar.org/battlefields/shiloh.html