History 46 World War, 1939-1945 33 Campaigns 14 Politics and government 10 Causes 7 Juvenile literature 6 Sources 6 World war, 1939-1945 6 Civilization 5 Battles 4 Biography 4 Foreign relations 4 Influence 4 World War, 1914-1918 4 Concentration camps 3 Revolutions 3 Underground movements 3 Z1 3 1918-1945 2 20th century 2 Aerial operations 2 Civilization, Medieval 2 Cold War 2 Equipment and supplies 2 History, Military 2 Holocaust, Jewish (1939-1945) 2 Knights and knighthood 2 Later Middle Ages 1100-1453 2 Napoleonic Wars, 1800-1815 2 Personal narratives 2