General Reference
American History National Museum of American History
American Memory - Library of Congress
Calisphere - A World of Primary Sources and More
National Archives and Records Administration
The Authentic History Center - Primary Sources from American Popular Culture
Atlas of United States Presidential Elections
Discovery to the 19th century
American Journeys- Early Exploration
Liberty- The American Revolution
Monticello- The Home of Thomas Jefferson
Voyages: the Transatlantic Slave Trade Database
19th Century- WWI
From Revolution to Reconstruction
WWI- 1929
1929-WWII
FDR Library - Great Depression Facts