The German invasion of France and Belgium in August 1914 came agonizingly close to defeating the French armies, capturing Paris and ending the First World War before the autumn leaves had fallen. The initial German strategy revolved around, and in part depended on, rapid victory over the French, but they were unable to deliver the knock-out blow they had planned - and the surprisingly fluid battles of the early days of the war deteriorated into the defensive, trench-based warfare which was to see the war drag on for another four years of unprecedented slaughter.

Ian Senior has woven together strategic analysis, diary entries, dramatic eyewitness accounts and interview transcripts from soldiers on the ground with consummate skill. He has produced a remarkable new narrative history that for the first time focuses on the experiences of French and German troops in the long hot summer of 1914 as the outcome of the war hung in the balance, revealing how the defiant French opposition and failings in the German invasion plans ultimately foiled the German war machine and changed the course of the war.