Economic conditions 98 Politics and government 69 History 58 Economic history 35 Social conditions 24 World War, 1939-1945 20 Foreign relations 19 more ... Civilization 16 Politique et gouvernement 16 Conditions économiques 14 Histoire 13 Diplomatic relations 12 Depressions 11 Social life and customs 10 Economic policy 9 Description and travel 8 World War, 1914-1918 7 Communism 6 Working class 6 polityka i rządy 6 Capitalism 5 Economic aspects 5 Emigration and immigration 5 Minorities 5 Population 5 Reconstruction (1914-1939) 5 Relations extérieures 5 Descriptions et voyages 4 Guerre mondiale, 1939-1945 4 Industrial policy 4 Labor 4 Labor and laboring classes 4 Labor movement 4 New Deal, 1933-1939 4 Polish people 4 Presidents 4 Statesmen 4 Travel 4 Unemployed 4 Chefs d'État 3 less ...