The stalemate produced by the battles of August and September 1914 transformed the character of warfare in Europe, for generals as much as for common soldiers. Throughout the nineteenth century, military theory had rested on the assumption of decisive battle. Battle had been conceived as having a definite beginning and end. Most importantly, it had long been held that battle produced clear winners and losers. Certainly, the war plans of 1914 rested on the assumption of battles that would prove nasty and brutish, but also decisive and short. But as the war on the Western Front descended into the trench system, the very meanings of “battle” and “the front” changed. Pitched battle in its conventional sense proved relatively rare in the conflict of 1914–18, mostly because of its horrendous cost in men and materiel when it did occur. But in the trenches, a grinding and inherently indecisive form of “combat” was supposed to be constant. The spatial configuration of warfare changed radically as well. Millions of men fought for four years along hundreds of kilometers of trenches, a far longer front than had ever existed in European military history.