World War 87 History 48 Campaigns 36 World war 20 World War, 1939-1945 16 Biography 15 Naval operations 9 Juvenile literature 7 Personal narratives 6 Submarine 6 Aerial operations 5 Causes 5 Army 4 Campaign 4 Generals 4 Japanese occupation 4 Military intelligence 4 Foreign relations 3 Pictorial works 3 Prisoners and prisons 3 Secret service 3 Underground movements 3 World War, 3 Bibliography 2 Cryptography 2 Diplomatic history 2 Equipment and supplies 2 Heads of state 2 Kriegsmarine 2 Malaya 2