Organized warfare began, along with Western civilization, in the Fertile Crescent between the Persian Gulf and the Mediterranean Sea. The people of that area were nomadic until the discovery of seeds that could be cultivated and animals that could be domesticated led to the establishment of settled communities.
Initially, military forces were organized to defend these communities from marauders; then, because of the pressures of increased population and herds, boundaries were pushed outward at the expense of neighboring people. Beginning around 3500 BC, the Middle East from Mesopotamia to Egypt was in constant turmoil as empires rose and fell.
The history of war can be broken into 7 time periods:
(1) Prehistoric Warfare (2) Ancient Warfare (3) Greco-Roman Warfare (4) Medieval Warfare (5) Modern Warfare (6) Nuclear Warfare (7) The War on Terrorism
War is a conflict involving the organized use of weapons and physical force by states or other large-scale groups.
Warring parties usually hold territory, which they can win or lose; and each has a leading person or organization which can surrender, or collapse, thus ending the war. Until the end of World War II, participants usually issued formal declarations of war.
To be officially considered a war, at least 1,000 soldiers (combined between the sides) must be killed in battle per year.
The media often refers to wars as "armed conflicts", "hostilities", "operations", and "police actions".