It was in fact a forced loan supported by a Government Bond. Because the Weimar Republic collapsed. It appears that when the new government took over these bonds which could be exchanged for the new government bonds, but at a discounted rate. All those that were converted were paid out over a period of time.
From what I have read, it appears that the whole world suffered for years to repay the cost of WW1. In the 1920’s America helped a great deal, as they had during the war by extending loans to the allies, but after the financial crash on Wall Street in 1929, America entered the great depression, which affected the whole world in the 1930’s.