This book focuses on some new issues associated with British appeasement policy in the 1930s. It looks particularly at how the artificial split between international history and military history has led to the over-simplification of the factors involved in formulating the appeasement policy. It argues that, contrary to anti-appeasement mythology, Britain was not left defenceless in 1939, having in fact a highly sophisticated aerial defence system for which Baldwin and Chamberlain have received little credit.Conversely, the disaster of 1940 was not a consequence of the sins of the British appeasers, but the result of a seriously misconceived French strategy, and brilliant German planning. The book further argues that Anglo-Czech relations between 1935 and 1938 showed that both the Foreign Office and anti-appeasers had deep rooted anti-Slav prejudices. However, new Czech research shows a more sympathetic understanding of how, and why, Britain adopted the appeasement policy. Important new Soviet sources are also considered, such as notably the Maisky Diaries (2016), for their relevance to British policy.