Territorial expansion History 9 Foreign relations 4 Imperialism 4 International relations 4 Influence 3 Political aspects 3 more ... Capitalism 2 Frontier and pioneer life 2 Nationalism 2 Race relations 2 Slavery 2 Antiquities 1 Attitudes 1 Cities and towns 1 Civil war 1 Colonies 1 Commerce 1 Conservatism 1 Cotton growing 1 Economic aspects 1 Economic development 1 Equality 1 Government relations 1 Indians of North America 1 Little Bighorn, Battle of the, Mont., 1876 1 Mexican War, 1846-1848 1 Oligarchy 1 Political and social views 1 Political culture 1 less ...