Chiefly, the hyper-inflation that occurred within the German economy after their nation was found [by the victorious alliance of nations] to be responsible for the destruction from WWI and made to pay reparations for that destruction.
Yes indeed. WWI was not initiated by Germany, although they did end up being the considered historical 'evil', and those of the group of nations planted the seedbed of what then followed. NOT an excuse for what happened but WWII cannot be discussed or described without the previous 2 + decades being part of the discussion.