Secret service World War, 1939-1945 History 174 Spies 81 Military intelligence 56 Service secret 54 Guerre mondiale, 1939-1945 53 more ... Underground movements 46 Cryptography 42 Campaigns 33 Intelligence officers 28 Intelligence service 28 Espionage 24 Espionage, German 19 Foreign relations 19 Deception 12 Electronic intelligence 12 Holocaust, Jewish (1939-1945) 12 Diplomatic history 11 Histoire 11 Espionage, British 10 Women 10 Women spies 10 Commando operations 9 Politics and government 9 Sabotage 8 Weltkrieg 8 Collaborationists 7 Espions 7 Nazis 7 less ...