<P> Friction arose between de Gaulle and Pétain over Le Soldat, a history of the French soldier which he had ghost - written and for which he wanted greater writing credit . He had written mainly historical material, but Pétain wanted to add a final chapter of his own thoughts . There was at least one stormy meeting late in 1926 after which de Gaulle was seen to emerge, white with anger, from Pétain's office . In October 1926 he returned to his duties with the Headquarters of the Army of the Rhine . </P> <P> De Gaulle had sworn that he would never return to the École de Guerre except as commandant, but at Pétain's invitation, and introduced to the stage by his patron, he delivered three lectures there in April 1927: "Leadership in Wartime", "Character", and "Prestige". These later formed the basis for his book The Edge of the Sword (1932). Many of the officers in the audience were his seniors, who had taught and examined him only a few years earlier . </P> <P> After spending twelve years as a captain, a normal period, de Gaulle was promoted to commandant (major) on 25 September 1927 . In November 1927 he began a two - year posting as commanding officer of the 19th chasseurs à pied (a battalion of élite light infantry) with the occupation forces at Trier (Treves). </P> <P> De Gaulle trained his men hard (a river crossing exercise of the freezing Moselle River at night was vetoed by his commanding general). He imprisoned a soldier for appealing to his deputy (member of parliament) for a transfer to a cushier unit, and when investigated initially tried to invoke his status as a member of the Maison Pétain, eventually appealing to Pétain to protect himself from a reprimand for interfering with the soldier's political rights . An observer wrote of de Gaulle at this time that although he encouraged young officers, "his ego...glowed from far off". In the winter of 1928 - 1929, thirty soldiers ("not counting Annamese") died from so - called "German flu", seven of them from de Gaulle's battalion . After an investigation, he was singled out for praise in the ensuing parliamentary debate as an exceptionally capable commanding officer, and mention of how he had worn a mourning band for a private soldier who was an orphan earned an exclamation of praise from the Prime Minister Raymond Poincaré . </P>

Who became seen as the leading banker to the world after the world war i