The Versailles Treaty demanded five billion gold marks in reparations from Germany, the instigators of WW1. This, oddly enough, was the exact sum the victorious Prussians demanded (and got) from France after winning the war of 1871. Receiving that sum over a few years caused a disastrous deflation and depression in Prussia based on speculation and land price rises. That sum of five billion gold marks was demanded by the Prussians because that was the exact sum Napoleon Bonaparte demanded of them when he conquered Prussia in the early 1800s. There's history between France and Germany...

Five billion gold marks is about $350 billion in today's money, allowing for inflation.