<p>This paper examines the intellectual radicalization of a prominent German civil rights activist who, over the course of a decade, increasingly aligned with far-right ideologies. It asks how public ostracism shapes the radicalization trajectories of public figures who adopt far-right positions: does it prompt reputational repair and moderation, or does it instead deepen ideological radicalization? Addressing the lack of an established framework for analyzing such cases, the paper tests the applicability of a radicalization model originally developed for Islamist violent extremism to a case of intellectual far-right radicalization. The study combines a thematic qualitative content analysis of the activist’s publications, interviews, and public responses with a quantitative analysis of media coverage from eleven national, six regional, and seventeen far-right media outlets to assess his claims of ostracization. The findings indicate that the activist’s radicalization was driven primarily by psychological vulnerabilities rooted in denied intellectual recognition, economic crises following ostracism, and an increasingly polarized “us versus them” worldview. Far-right media provided validation and an alternative platform, thereby enabling and reinforcing ideological alignment. Drawing on a single case, the analysis suggests that models developed for violent (Islamist) extremism can be adapted to understand non-violent intellectual far-right radicalization, as similar psychological and social mechanisms appear to operate across ideological domains and across violent and non-violent outcomes. This has implications for both radicalization research and ongoing debates about “cancel culture” and societal responses to far-right public figures. The case indicates that ostracism alone – exemplified by the German “firewall” against the far right – is unlikely to prevent radicalization without accounting for the enabling role of far-right media ecosystems.</p>