While it may be most known for its huge role in battle in WWI, trench warfare was first established during the American Civil War. With improvements in weapon technology resulting in greater accuracy of rifles and cannons, soldiers no longer needed to be on the ground level to fight at their best. Along with their guns, men carried shovels digging miles of elaborate trenches in which they sheltered, lived and fought from. We at Cockpit USA recently came across this short film from History.com on the evolution of trenches - check it out for an interesting look at the changing texture of warfare.