Between 1922 and 1924, the Austrian Federal Government tried to ban the newly opened crematorium in the »red city« of Vienna. However, the Social Democratic mayor of Vienna refused to obey the instructions of the Christian Social Federal Minister. Because the competency rules of the republican, new Constitution (B-VG) did not come into force at that time, a legal dispute arose between the Federal Government and Vienna (as State). The Constitutional Court (VfGH) ultimately decided the dispute in favor of Vienna. However, the federal government tried to prevent the crematorium with two further motions (concerning a supposed conflict of competencies between the federal government and Vienna, and because of the alleged unconstitutionality of the State Constitution of Vienna). In these cases too, the Constitutional Court ruled in favor of Vienna, but without answering the main question of whether the cremation was legal in Austria. In addition to the concrete legal situation, the case also represented an important chapter of the »Kulturkampf« of that time, which, however, was fought out on the ground of Constitutional Law. In the article, I describe both the public and legal debates, as well the legal situation and the processes by using primary sources. The famous legal theorist Hans Kelsen acted as a consultant at the Constitutional Court in all three processes. Therefore, the question is also to be analyzed whether the decisions corresponded or contradicted the »Pure Theory of Law« of Kelsen, and whether the »self-restrained« judicature of the Constitutional Court is to be regarded as an »activist« one in the sense of Kelsen's legal doctrine and the historical context of the time.