Trench warfare caused enormous numbers of casualties.
At least initially in World War I, forces mounted attacks from the trenches, with bayonets fixed to their rifles, by climbing over the top edge into what was known as “no man’s land,” the area between opposing forces, usually in a single, straight line and under a barrage of gunfire.
Not surprisingly, this approach was rarely effective, and often led to mass casualties.
Later in the war, forces began mounting attacks from the trenches at night, usually with support of covering artillery fire. The Germans soon became known for effectively mounting nighttime incursions behind enemy lines, by sending highly trained soldiers to attack the trenches of opposing forces at what they perceived as weak points.
If successful, these soldiers would breach enemy lines and circle around to attack their opponents from the rear, while their comrades would mount a traditional offensive at the front.
The brutality of trench warfare is perhaps best typified by the 1916 Battle of the Somme in France. British troops suffered 60,000 casualties on the first day of fighting alone
READ MORE: Why Was the Battle of the Somme So Deadly?
Disease and ‘shell shock’ were rampant in the trenches.
With soldiers fighting in close proximity in the trenches, usually in unsanitary conditions, infectious diseases such as dysentery, cholera and typhoid fever were common and spread rapidly.
Constant exposure to wetness caused trench foot, a painful condition in which dead tissue spread across one or both feet, sometimes requiring amputation. Trench mouth, a type of gum infection, was also problematic and is thought to be associated with the stress of nonstop bombardment.
As they were often effectively trapped in the trenches for long periods of time, under nearly constant bombardment, many soldiers suffered from “shell shock,” the debilitating mental illness known today as post-traumatic stress disorder (PTSD).
It’s likely all of these factors, which stemmed from the widespread use of trench warfare, made World War I the deadliest conflict in global history to that point. It’s believed that as many as one in 10 of all fighting forces in the conflict were killed.
It was also the first conflict in world history to have more deaths caused from combat, rather than from disease spread during fighting.
Trench warfare was also employed in World War II and in the Korean War to some degree, but it has not been used regularly during conflicts in the ensuing decades.
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