<P> Initiated by French Prime Minister Raymond Poincaré , the invasion took place on 11 January 1923 . General Alphonse Caron 's 32nd infantry corps under the supervision of General Jean - Marie Degoutte carried out the operation . Some theories state that the French aimed to occupy the centre of German coal , iron , and steel production in the Ruhr area valley simply to get the money . Some others state that France did it to ensure that the reparations were paid in goods , because the Mark was practically worthless because of hyperinflation that already existed at the end of 1922 . France had the iron ore and Germany had the coal . Each state wanted free access to the resource it was short of , as together these resources had far more value than separately . ( Eventually this problem was resolved in the post-World War II European Coal and Steel community . ) </P>
when did france and belgium invade the ruhr
11 January 1923