Social Studies - 2018-19

USI.8a - Territorial Expansion after 1801

The student will apply social science skills to understand westward expansion and reform in America from 1801 to 1861 by  

a) describing territorial expansion and how it affected the political map of the United States, with emphasis on the Louisiana Purchase, the Lewis and Clark expedition, and the acquisitions of Florida, Texas, Oregon, and California; 

Adopted: 2015



Between 1801 and 1861, exploration was encouraged as America underwent vast territorial expansion and settlement.


New territories added to the United States after 1801 

 Louisiana Purchase 

o Jefferson bought land from France (the Louisiana Purchase), which doubled the size of the United States. 

o In the Lewis and Clark expedition, Meriwether Lewis and William Clark explored the Louisiana Purchase and the Oregon Territory from the Mississippi River to the Pacific Ocean. 

 Florida 

o Spain gave Florida to the United States through a treaty. 

 Texas 

o Texas was added to the United States after it became an independent republic. 

 Oregon 

o The Oregon Territory was divided by the United States and Great Britain. 

 California 

o War with Mexico resulted in California and the southwest territory becoming part of the United States. 


Updated: May 16, 2018