In 1940, the future of Europe was decided not only on the battlefield, but also in cabinet meetings, diplomatic exchanges and negotiations conducted under the pressure of military defeat. Could the war still be brought to an end through negotiation? What terms would Germany accept, and what concessions could Britain and France contemplate? How did the possibility of peace give way to decisions that prolonged and widened the conflict? Drawing on diplomatic correspondence, parliamentary debates and contemporary records, historian Daniel Arden reconstructs the critical decisions of 1940, from the peace initiatives of the winter and the Norwegian campaign to the fall of France, the Dunkirk evacuation and Britain's determination to continue fighting. The narrative examines Churchill's wartime coalition, Roosevelt's diplomatic mission, the French armistice, the confrontation over the French fleet, the Battle of Britain and the growing importance of American assistance. It also follows the expansion of the conflict across Europe and the Mediterranean. Accompanied by an extensive collection of historical photographs, detailed source notes, a chronology and profiles of key figures, this study explores how governments weighed diplomacy, national survival and military necessity at a moment when the outcome of the war remained uncertain. A documented account of the choices that shaped 1940—and the consequences of refusing to bring the war to an end.