A detailed account and analysis of the 1914 western campaign that reconstructs troop movements, strategic plans, and critical decisions leading to the Allied counterstroke that halted the German advance. It traces competing doctrines and operational errors, assesses the distribution and quality of forces, and follows the retreat, the concentration of reserves around the capital, and the counteroffensive across the Marne sector. The narrative combines battlefield description, maps, and contemporary memoirs to evaluate the roles of key commanders, logistical and command factors, contested explanations of success and failure, and concludes with a measured summing-up and documentary notes.