defence of Arras, the key to the sea and again halted the German advance there, which led to the front's stabilisation and the start of trench warfare. 1915 Promoted to colonel, he took command of the 90th Brigade which witnessed on 22 April 1915 the first chemical attack in history. His troops stood firm in the following weeks and retook lost ground. 1916 He was made général de brigade in 1916 and led the , which fought in the Battle of Verdun and the Battle of the Somme. 1917 In early 1917, he led his division in the Champagne region and threw back the Germans back to their lines before the Chemin des Dames attack. He was to command an infantry corps in Italy but was called in early November 1917 to become the military chief of staff in Clemenceau's second government in what was to be nicknamed the Ministère de la Victoire. In government He proved himself essential to the French command's reorganisation and was Clemenceau's influential right-hand man from 1917 to 1920, thus participating extensively in the Allied victory of 1918. In January 1920, he became commander of the 30th Infantry Corps occupying in Rhineland in Wiesbaden. He remained at his command until 1925 when he left the army, resenting the contemporary political and military leaders who alienated him for his criticism of the appeasement policy toward Germany and for his unrelenting loyalty to Clemenceau in 1920. Retirement From 1925 to his death in 1943, Mordacq wrote more than twenty books and published dozens of articles in influential reviews to promote Clemenceau and his actions in the troubled days from November 1917 to 1920, explaining the choices and reforms which were made in order to achieve military and political victory. He criticised former friend Philippe Pétain's promulgation of racial laws in 1941. Mordacq was found dead in the Seine under the Pont des Arts on 12 April 1943. His last literary work on World War I, part 4 in the series "The Great Hours of War", titled, "1917, The Year of Anguish", was released just after the onset of World War II, in 1940. Works (titles translated from French) Mordacq, Captaine, The War in Morocco: Tactical Lessons of the two Franco-Moroccan (1884) and Spanish-Moroccan (1859-1860) Wars, Paris: Lavauzelle, 1896 Mordacq, Captaine, "Pacification of Upper Tonkin: History of the last military operations, Northern Columns (1895-1896)", Paris: Chapelat, 1901 Mordacq,