Territorial expansion 66 History 34 Foreign relations 12 Frontier and pioneer life 12 Politics and government 8 Slavery 6 Expansion territoriale 5 more ... Indians of North America 5 Colonial question 4 Government relations 4 Imperialism 4 Eastern question (Far East) 3 Explorers 3 Extension to the territories 3 Histoire 3 Historical geography 3 Mexican War, 1846-1848 3 Public opinion 3 Race relations 3 Causes 2 Diplomatic relations 2 Discoveries in geography 2 Discovery and exploration 2 Filibusters 2 Insular possessions 2 Land settlement 2 Louisiana Purchase 2 Presidents 2 Public lands 2 Social aspects 2 Sources 2 Spanish-American War, 1898 2 20e s. (1ère moitié) 1 African American 1 African Americans 1 Américain d'origine hispano-américaine (peuple) 1 Américains d'origine latino-américaine 1 Annexation 1 Annexation to the United States 1 Anti-imperialist movements 1 less ...