The American Civil War usnered in a new era in land warfare. In this war, mass armies first experienced the widespread impact of industrial techlogy. The response of the Civil War soldier and field commanders to the techlogy of the Industrial revolution shaped tactical and strategic organization into new forms. If it was, in fact. the first of the great modern wars, it stands before us an evolutionary monument. The devastating increase of fire power. Brought on by the introduction and standardization of the muzzle loading rifle musket and the rifled artillery, doomed the opened frontal assault and ushered in the entrenched battlefield. The defense would dominate the offense. No where was the superior power of the fortified defense better illustrated than at the Battle of Fredericksburg. There would occur an evolution in the employment of entrenchments during the Wilderness campaign, t only in a defensive posture, but also as an essential adjunct to the attack. Advanced techlogy in weaponry and the trench, due to the heightened fire power, would dominate the battlefields of the Civil War. They would continue to do so at least through the First World War. This study will attempt to illustrate the evolution of entrenchments during the Civil War Campaigns of Fredericksburg and The Wilderness. Tactical lessons learned from these campaigns would have visionary application to the battlefields of World War I. In conclusion, we will show the disregard for, these lessons learned by the leaders of the World War.