37
Lesson 37 of 84 · Westward Expansion
The Oregon Trail
Ancient Mesopotamia, between the Tigris and Euphrates rivers, is called the cradle of civilization. The Sumerians invented writing, the wheel, and early forms of government around 3500 BCE.
Key Facts
1
Cause and effect explain why things happen.
2
Oral histories preserve community stories.
3
Primary sources come from the time of the event.
Check Your Understanding
Question 1
1 of 2What tool puts events in order?