c. 3500 BCE Urban growth accelerates at Uruk Uruk emerges as one of the world's earliest major cities, marking a decisive phase in Mesopotamian urban civilization. c. 3300 BCE Proto-cuneiform writing appears The earliest known writing systems in Mesopotamia develop for accounting and administrative use. c. 2900 BCE Early Dynastic city-states consolidate Independent city-states such as Ur, Uruk, Lagash, and Kish dominate southern Mesopotamian politics. c. 2600 BCE Royal Cemetery of Ur flourishes The elite burials at Ur reflect the wealth, hierarchy, and ritual culture of early Mesopotamian states. c. 2334 BCE Sargon founds the Akkadian Empire Sargon of Akkad creates one of the first territorial empires in recorded history. c. 2254 BCE Naram-Sin reaches imperial high point Under Naram-Sin, Akkadian power expands and imperial kingship is exalted in new ways. c. 2154 BCE Akkadian Empire collapses The Akkadian imperial order breaks down amid internal strain and external pressure. c. 2112 BCE Ur-Nammu establishes the Third Dynasty of Ur Ur-Nammu reunifies much of southern Mesopotamia and founds the Ur III state. c. 2100 BCE Code of Ur-Nammu is issued One of the earliest known law codes is promulgated under the rulers of Ur III. 2004 BCE Ur III falls to invading forces The Third Dynasty of Ur collapses, ending the last great Sumerian-led state. c. 1894 BCE Amorite dynasty is established at Babylon An Amorite ruling house takes power in Babylon, beginning the dynasty later associated with Hammurabi. c. 1792 BCE Hammurabi becomes king of Babylon Hammurabi begins the reign that will make Babylon the leading power in southern Mesopotamia. c. 1754 BCE Code of Hammurabi is compiled The Babylonian law collection associated with Hammurabi becomes one of the most famous legal texts of the ancient world. 1595 BCE Hittites sack Babylon A Hittite raid captures Babylon and contributes to the end of the First Babylonian Dynasty. c. 1365 BCE Assyria rises under Ashur-uballit I Assyria reemerges as a major regional power in the Middle Assyrian period. 911 BCE Neo-Assyrian expansion begins under Adad-nirari II The accession of Adad-nirari II marks the beginning of the Neo-Assyrian Empire's rise. 722 BCE Assyria captures Samaria The fall of Samaria demonstrates the military reach of the Neo-Assyrian Empire in the Levant. 612 BCE Nineveh falls A coalition of Babylonians and Medes captures Nineveh, ending Assyrian imperial dominance. 539 BCE Cyrus the Great captures Babylon The Persian conquest of Babylon brings Mesopotamia under Achaemenid rule. 331 BCE Alexander the Great enters Babylon Alexander's conquest brings Mesopotamia into the Hellenistic world.