Radical activist documentaries are frequently agitational and ‘present tense’, reflecting their typical aim of shifting audiences into action around a specific contemporary cause or struggle. But a radical activist approach to making films about history poses problems distinct from those confronting film-makers producing a non-radical historical documentary or a ‘present-tense’ radical activist film. By adopting an approach to such film-making that embraces elements of archival film-making and essayistic self-portraits, along with select fictionalising devices, a new form of radical activist historical documentary emerges. This outcome develops our understanding of how radical activist documentary can function and how experimental approaches to documentary form can enrich historical documentary practice.