OpenStax
Open Stax: American Foreign Policy 1890 1914: Turner, Mahan, and Roots of Empire
Examines the development of American foreign policy in the latter part of the 1800s, and what Frederick Jackson Turner and Alfred Thayer Mahan did to further American imperialistic interests.
Gilder Lehrman Institute of American History
Gilder Lehrman Institute: History Now: Empire Building
[Free Registration/Login Required] A lengthy essay about American focus on foreign affairs after the Civil War, expanding particularly in the late 19th century. Read about U.S. exploits in the Caribbean, Latin America, and the Pacific...
US National Archives
Our Documents: Check for the Purchase of Alaska (1868)
Interactive images of two documents important in Alaska's history: the check written for its 1868 purchase from Russia and the Russian Treaty of Cession (an English transcript is provided), which concluded the deal.
Encyclopedia Britannica
Encyclopedia Britannica: Andrew Johnson
This site from Britannica provides information on President Andrew Johnson.
Country Studies US
Country Studies: Ambivalent Empire
With the purchase of Alaska in 1867, the United States embarked on the road of building an empire. From Alaska to the Spanish-American War to the Philippine Islands, the U.S. grew as an imperial nation throughout the latter half of the...
Independence Hall Association
U.s. History: Early Stirrings
American desire for overseas expansion began as early as the purchase of Alaska from Russia. See what other actions were taken in the latter part of the 19th century, and find out why this imperialist view was taking hold.
Other
Impeachment of Andrew Johnson: William H. Seward
Short biography of the man who served as secretary of state under President Lincoln and Johnson.