army

army Organized group of soldiers trained to fight on land, usually rigidly hierarchical in structure. The first evidence of an army comes from Sumer in the third millennium bc. The use of cavalry was a Hittite development and the Assyrians added archers and developed siege machines. In the Middle Ages, major improvements were made to armour and weapons. The short-term feudal levy by which armies were raised proved inflexible, and this led to the use of mercenaries. Heavy cavalry was replaced by a combination of infantry and archery. The end of the Hundred Years' War saw the inception of royal standing armies and an end to the chaos caused by mercenary armies. Muskets and bayonets replaced the combinations of longbow, pike and infantry, and artillery was much improved. In the French Revolutionary Wars, a citizen army was raised by conscription and contained various specialist groups. Other European armies followed suit and the age of the mass national army began. The machine gun caused deadlock in the World War I trenches, and was broken only by the invention of the tank. World War II saw highly mechanized and mobile armies whose logistics of supply and support demanded an integration of the land, sea and air forces. Since World War II, nuclear weapons have been deployed both tactically and strategically, and again the nature of weaponry has determined an army's structure.