At the end of World War One, the losers and starters of that conflict were correctly punished by the Treaty of Versailles in 1919 and were expected to pay a relatively tiny amount in reparations.
They lost territory.
They were heavily restricted in what armaments they were permitted.
The following Weimar government was pathetic and there was great suffering in the country.
The heavily misplaced sentiments of resentment alongside insane rightist claims that 'the German Army had not lost in the field' and that 'Versailles was a monstrosity' fuelled the rise of Naziism and the ridiculous creation of Jewish scapegoats.
Much of this came about in the aftermath of the Wall St Crash of 1929.
It is now generally accepted by revisionist historians that the Versailles Treaty was unfair to Germany.
It was not! Warmongering nations must be punished.
The causes of World War Two were principally derived from three things - all of which are common mistakes:
1) The first was claiming 'a peace dividend' as if no other wars could possibly ever happen. The damage caused by this policy across Western nations cannot be overstated.
2) Accepting all of Hitler's abuses of the Treaty. He armed, he began an airforce and he took over disputed lands which had been taken away from Germany.
3) That acceptance of rearmament and allowing Hitler's 'salami slicing' tactics of lands claimed had to be challenged - and it was not. This was cowardice of the worst type - and what a price had to be paid for it.
Military force, employed at the very start of Hitler's machinations would inevitably have stopped Adolph in his tracks. WW2 would not have happened - in Europe, at least.
Extreme weakness was displayed by war-weary nations who were also afraid because they doubted that their weaponry was good enough any longer. It wasn't - Hitler had been permitted a head start.
The pathetic League of Nations was simply ignored by Hitler as it showed no teeth.