The Constitution of the German Reich , usually known as the Weimar Constitution (Weimarer Verfassung) was the constitution that governed Germany during the Weimar Republic (1919–1933). The constitution declared Germany to be a democratic parliamentary republic with a legislature elected under proportional representation. Universal suffrage was established, with a minimum voting age of 20. The constitution technically remained in effect throughout the existence of the Third Reich from 1933 to 1945.