31st century BC

(32nd century BC - 31st century BC - 30th century BC - other centuries)

(5th millennium BC - 4th millennium BC - 3rd millennium BC)

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Events:

Significant persons:

• Ur-nina[?] first king of Lagash in Mesopotamia

Inventions, Discoveries, Introductions:

• Chinese ideograms
• Drainage and sewage system in India
• Dams, canals, stone sculptures[?] using inclined plane and lever in Sumeria
• Pyramids in Ancient Egypt
• Copper was in use, both as tools and weapons.
• Crude writing existed in Egypt, and cuneiform writing was invented in Mesopotamia.