Why were the Germans unhappy with the 1918 Peace Treaty?
Because it reduced the size of Germany, and made them pay reparations they could not afford, damaging their economy. EDIT – “Dangerous” does not demonstrate an understanding of German politics from the creation of Germany (1871) to the start of the First World War. The majority of the people of Germany had every justification to be “sore losers”, as the version of democracy in use in Germany was a bit of a joke. Germany was effectively “Greater Prussia”, dominated by an autocratic regime who ignored and marginalised other Germans with impunity. Bismarck removed Catholics from civil service, banned church weddings, had socialists arrested (which did not have the desired effect – socialists actually gained seats in the Reichstag.) but the parliament was in effect dominated by Prussian parties until the 1912 election, and by Prussian representatives, no matter what their party.