Anti-feminist and anti-gender ideologies—and their basis in hostility and hatred towards women and LGBTQI* people—have long been an overlooked factor in analysing radicalisation and violent extremism. Both ideologies strongly appeal to groups organised around exclusionary principles because they provide language and a framework for the defence of hierarchical structures in society. This trend is increasingly manifesting itself across a spectrum of violence. Despite a striking prevalence of anti-feminism and anti-gender attitudes within extremist worldviews, these motives have been considered at best secondary when analysing extremist attacks and groups. Yet, for extremist actors, they constitute a core element of their ideologies, a relevant area of recruitment within and outside extremist scenes, and an opportunity for strategic alliances.