81
Lesson 81 of 84 · World History
The Transatlantic Slave Trade
Westward expansion in the 1800s transformed the U.S. from an Atlantic nation to a Pacific one. The Oregon Trail, Gold Rush, and Homestead Act drove this movement.
Key Facts
1
Primary sources come from the time of the event.
2
Historians use evidence to support claims.
3
Timelines show events in order.
Check Your Understanding
Question 1
1 of 2What is a primary source?