5500–4000 BCE : Sumerian civilization established in the Euphrates valley in southern Mesopotamia (now Iraq).
3650–1400 BCE : Minoan and other early Aegean civilizations.
3100 BCE : First pharaoh unites Upper and Lower Egypt.
2600–1900 BCE : Mature period of the Indus valley civilization.
2580–2560 BCE : Great Pyramid of Giza built.
2070 BCE : Xia dynasty in China.
2000 BCE : Preclassic period of Mayan civilization in Mesoamerica.
1754 BCE : Code of Hammurabi, an early legal system, created in the Babylonian empire.
1650 BCE : Hittite kingdom emerges in Turkey.
1600 BCE : Shang dynasty emerges in the middle valley of the Yellow River in China.
1600–1500 BCE : Olmec civilization established in modern-day Mexico.
1550–1077 BCE : New kingdom of Egypt rules empire stretching from the Levant to Nubia.
1500–800 BCE : Vedic Age: creation of ancient Hindu scriptures in India.
1070 BCE : Kingdom of Kush established in modern-day Sudan.
1000 BCE : Golden age of Phoenician cities, including Tyre and Sidon.
911–612 BCE : Neo-Assyrian empire in the Tigris valley.
900–200 BCE : Chavin civilization in modern Peru.
800–400 BCE : D’mt kingdom in Ethiopia.
c . 550 BCE : Cyrus the Great of Persia founds Achaemenid empire.
510–323 BCE : Classical period of ancient Greece.
509 BCE : Roman republic established.
331 BCE : Alexander the Great of Macedon defeats Persia’s Achaemenid empire and goes on to rule from the Adriatic Sea to the Indus River, spreading Hellenistic influence far and wide.
321–185 BCE : Mauryan empire in India.
300 BCE : Construction of the library of Alexandria, the ancient world’s largest.
221 BCE : The Qin dynasty (followed by the longer-lasting Han dynasty) establishes China’s first united empire.
212 BCE : Roman citizenship granted to all free inhabitants of the empire.
100 BCE : Rome becomes the largest city in the world.
150–650 CE : Teotihuacan becomes the largest city in the pre-Columbian Americas, with a peak of 125,000 inhabitants.
300–1200 CE : Ghana empire established in modern-day Mauritania and Mali.
410: Visigoths sack Rome; the final fall of the western Roman empire follows in 476.
661–750: The Umayyad caliphate is the largest empire in terms of area up to this date, stretching from modern-day Georgia, Uzbekistan and Pakistan across the Arabian peninsula and North Africa and up into Spain and Portugal.
1055: Seljuk Turks capture Baghdad.
c . 1200: Incas settle in Andean valley in Peru.
1200–1400: Mississippian Culture in North America reaches its peak, with extensive areas along the Mississippi River under cultivation, and towns of up to 20,000 people.
1206: Foundation of sultanate of Delhi.
1211: Mongols begin conquests of northern China and across Eurasia.
1368: Ming dynasty established in China.
1393: Timur (aka Tamerlane) sacks Baghdad.
1405: Beginning of Zheng He’s voyages in Indian Ocean.
1438: Beginning of period of Inca conquests.