In warfare the battles grab most of our attention. But there is a secret history to every war; a hidden world of spies, double agents, assassins and saboteurs. Secret History: World War I explores how each side tried to keep secrets from the enemy, while at the same time trying to break their codes and disrupt their missions. From invisible ink and secret codes, to propaganda and battle tactics, this book covers all of the main ways each side tried to outwit the other - and win the war.

Secret History is a series of books exploring the six major conflicts of the 20th century.

This book is part of a book series called Secret History .

There are 48 pages in this book. This book was published 2014 by Hachette Children's Group .

Chris Oxlade is an experienced writer of children's non-fiction and specialises in scientific subjects.

This book has the following chapters:

• 1: World War I
• 2: War Breaks Out
• 3: German Spies In Britain
• 4: Invisible Messages To Germany
• 5: Black Tom
• 6: British Counter-Espionage
• 7: Allied Spies
• 8: Female Spies
• 9: Codes And Ciphers
• 10: Code-Breakers
• 11: The Code Talkers
• 12: Secret Weapons In Battle
• 13: Secret Weapons In The Air
• 14: Submarine Warfare
• 15: Tunnelling Under The Trenches
• 16: Propaganda And Censorship
• 17: The Zimmerman Telegram
• 18: The Hindu-German Conspiracy
• 19: The End Of The War
• 20: Timeline
• 21: Glossary
• 22: Further Information
• 23: Index