After World War I, the German Empire became a republic informally known as Weimar Republic, a change which was reflected in a new flag of Germany that in fact was older than the former one, dating back to early 19th century democratic movements. In the Paris Peace Conference, the outbreak of the war was blamed on Germany and other Central Powers allies. These nations, which by now had new governments, were banned from the 1920 Summer Olympics. While all other banned nations were invited again for the 1924 Summer Olympics, held for the second time in Pierre de Coubertin's home town of Paris, the ban on Germany was not lifted until 1925. This was likely related to French Occupation of the Ruhr and the Rheinland between 1923 and 1925.