The Weimer Republic had to face several problems as soon as it came to power.
the humiliating treaty of Versailles put the entire blame of the defeat of the war on Germany and so inflicted high remunerations on it.
their rise also coincided with the revolutionary uprising of the Spartacist League on the pattern of the BolshevikRevolution in Russia. The WEimer government had to take steps to crush down all the oppositions like the FreeCorps
they also had to face the effects of teh economic depression
The Weimar republic was politically fragile for the following reasons:
i) The inherent defects in the constitution made it vulnerable to dictatorship.
ii) The system of proportional representation made achieving a majority by any one party an impossible task and led to coalitions.
iii) Article 48 gave the President powers to impose emergency, suspend civil rights and rule by decree.
iv) The system led to formation of twenty different cabinets for the duration of Weimar republic and gradually eroded the confidence of people in democratic means.