Mesopotamia, often referred to as the world's first civilization, emerged between the Tigris and Euphrates rivers, primarily in modern-day Iraq and parts of Iran, Syria, and Turkey. It was characterized by its complex society, including organized governments, social classes, and innovations like writing, irrigation, and trade. Various kingdoms, including the Sumerians, Akkadians, Babylonians, and Assyrians, played vital roles in shaping its history and cultural development.