Trench warfare is a type of land warfare using occupied lines largely comprising military trenches , in which combatants are well-protected from the enemy's small arms fire and are substantially sheltered from artillery. It became archetypically associated with World War I — , when the Race to the Sea rapidly expanded trench use on the Western Front starting in September Trench warfare proliferated when a revolution in firepower was not matched by similar advances in mobility , resulting in a grueling form of warfare in which the defender held the advantage.
The area between opposing trench lines known as " no man's land " was fully exposed to artillery fire from both sides. Attacks, even if successful, often sustained severe casualties. The development of armoured warfare and combined arms tactics permitted static lines to be bypassed and defeated, leading to the decline of trench warfare after the war. Following World War I, "trench warfare" became a byword for stalemate, attrition , sieges , and futility in conflict.
Field works have existed for as long as there have been armies. Trench warfare was also documented during the defence of Medina in a siege known as the Battle of the Trench AD. The architect of the plan was Salman the Persian who suggested digging a trench to defend Medina. There are examples of trench digging as a defensive measure during the Middle Ages in Europe , such as during the Piedmontese Civil War , where it was documented that on the morning of May 12, , the French soldiers, having already captured the left bank of the Po river and gaining control of the bridge connecting the two banks of the river, and wanting to advance to the Capuchin Monastery of the Monte, deciding that their position wasn't secure enough for their liking, then choose to advance on a double attack on the trenches, but were twice repelled.
Eventually, on the third attempt, the French broke through and the defenders were forced to flee with the civilian population, seeking the sanctuary of the local Catholic church, the Santa Maria al Monte dei Cappuccini , in Turin, also known at that time as the Capuchin Monastery of the Monte. In early modern warfare , troops used field works to block possible lines of advance. The Crimean War — saw "massive trench works and trench warfare", [ 17 ] even though "the modernity of the trench war was not immediately apparent to the contemporaries".
Union and Confederate armies employed field works and extensive trench systems in the American Civil War — — most notably in the sieges of Vicksburg and Petersburg — , the latter of which saw the first use by the Union Army of the rapid-fire Gatling gun , [ 19 ] the important precursor to modern-day machine guns.
