<p>This paper investigates the historical reception of Kantian philosophy in the German Democratic Republic (GDR) and explores its contested role in the ideological erosion of Marxism–Leninism. Responding to Hans Heinz Holz’s provocative claim that “revisionists are always Kantians,” the study examines whether Neo-Kantianism contributed to the theoretical and political decline of socialism. The paper traces how Kant’s legacy evolved from initial ideological rejection to nuanced historicization and academic engagement. The analysis shows that while Kant was increasingly recognized for his contributions to Enlightenment thought, and dialectical development (and later even for his epistemology), his philosophy was also persistently framed as a precursor to revisionist deviations within the socialist tradition. However, the study demonstrates that there was no genuine Neo-Kantian revival within the GDR’s philosophical discourse. Rather, the growing interest in Kant reflected deeper material and institutional transformations, including the weakening of theoretical coherence in late socialism. The paper concludes that Kant or Kantian philosophy did not “kill” socialism. Instead, practical revisionism—driven by political, social, and economic contradictions—played a more decisive role in the ideological fragmentation of socialist states.</p>