4th millennium BC

• City of Ur in Mesopotamia (40th century BC).
• Naqada[?] culture on the Nile, 4000-3000 BC.
• Civilization of Crete (38th century BC).
• Civilization of Sumeria, cities-state (36th century BC).
• First to Fourth dynasty of Kish in Mesopotamia.
• Beginning of desertification of Sahara ( 35th century BC).
• Unification of Egypt, 3100 BC.

Significant persons:

• �tzi the Iceman lived circa 3300 BC.
• Ur-nina[?] first king of Lagash in Mesopotamia (31st century BC).

Inventions, Discoveries, Introductions

• Begin of urbanisation in Mesopotamia with the Sumerians.
• First cities in Egypt (35th century BC).
• First writings in the cities of Uruk and Susa (cuneiform writings). Hieroglyphs in Egypt.
• Potter's wheel[?] used in Middle East.
• Sails used in the Nile.

Centuries

• 40th century BC
• 39th century BC
• 38th century BC
• 37th century BC
• 36th century BC
• 35th century BC
• 34th century BC
• 33rd century BC
• 32nd century BC,
• 31st century BC