World War, 1914-1918 History 42 Politics and government 29 Foreign relations 22 Causes 20 Soldiers 13 Campaigns 11 more ... Guerre mondiale, 1914-1918 11 Diplomatic history 8 History, Military 7 Social conditions 6 World War, 1939-1945 6 Regimental histories 5 Aerial operations, German 4 Economic aspects 4 Economic conditions 4 Histoire 4 Influence 4 Intellectual life 4 Personal narratives, German 4 Politique et gouvernement 4 Employment 3 Families 3 Generals 3 Histoire militaire 3 Military campaigns 3 Peace 3 Psychological aspects 3 War 3 Women 3 less ...