World War, 1939-1945 123 History 37 Campaigns 24 Causes 15 World War 14 World war, 1939-1945 9 Sources 8 Biography 7 Economic aspects 7 Diplomatic history 6 Personal narratives 6 Aerial operations 5 1918-1945 4 Armed Forces 4 Foreign relations 4 Great Britain 4 Secret service 4 Tank warfare 4 1939-1945 3 Aerial operations, British 3 Equipment and supplies 3 Historiography 3 Military 3 Military art and science 3 Military leadership 3 Naval operations 3 Naval operations, British 3 Personal narratives, British 3 World war 3 Admirals 2