On Friday 30 September 1938, the prime minister, Neville Chamberlain, arrived back in Britain after a two-day conference in Munich with Hitler, Mussolini and the French prime minister, Edouard Daladier. Brinkmanship is a word that has been bandied about a lot recently with the sparring between Donald Trump and Kim Jong-un, but back in the autumn of 1938, only twenty years after the end of the Great War, Europe really was on the brink of conflict once again. The previous day, France and Britain had agreed that the predominantly German-speaking part of Czechoslovakia known as the Sudetenland should be peacefully annexed by Germany. The Czechs were entitled to resist, but they could no longer expect the support of Britain and France. The land in question played host not only to most of Czechoslovakia’s defences but also to much of its natural resources. As part of the deal, Hitler assured all parties he had no further territorial ambitions.