The book "Spying for Wellington" by British Military Intelligence in the Peninsular War provides a comprehensive overview of the role of espionage during this period of history. The author, John H. G. Leigh, uses primary sources such as letters, diaries, and official records to explore how spies were used to gather information about the enemy's movements, strength, and plans. He also examines the challenges faced by these spies, including capture, torture, and execution. The book begins with an introduction to the historical context of the Peninsular War, which was fought between 1807 and 1814 between Spain and a coalition of Britain, Portugal, and other allies against Napoleon's France. The author explains that the war was a defining moment in European history, shaping the modern political landscape of the continent. The first chapter delves into the early days of espionage, describing how spies were used to gather information on the enemy's movements and intentions.

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