The Quuuuuill made a great general response, but a couple important specifics:
- While he did touch on it, at the end of WWI, Germany had a revolution, the November Revolution. During the latter part in 1919 the Social Democratic Party, SPD, won the election, and their candidate, Friedrich Ebert, became president. His administration proceeded to arm paramilitaries such as the Freikorps to brutally stop the revolution. This included mass executions and targeted executions of communists such as Rosa Luxembourg.
This ultimately resulted in the liberal, anti-communist character of Weimar Germany which created the conditions for fascism.
- In the lead up to the elections of 1933, NSDAP ran Hitler. The communist part, KPD, and SPD talked about the necessity to beat hitler, and agreed to run 1 candidate to avoid splitting the vote. The SPD then proceeded to renominate the current president Hindenburg, an extremely conservative aristocrat and promoted unity and stability in all of their campaigning.
The KPD, ever cursed with Casandra Syndrome, ran their own candidate and campaigned on “A vote for Hindenburg is a vote for Hitler, a vote for Hitler is a vote for war”
And then Hindenburg won, with just over 50% of the vote. And then in the name of unity and stability, proceeded to make Hitler Chancellor and put nazis into other positions of power, setting them up to trivially coup the government.