In this article, the author focuses on the women of the National Union of Women Teachers (NUWT) who were a particularly important group of professional women workers, whose politics illuminated themes which were current in the feminist history-writing of the 1980s and 1990s. What the author found particularly striking about the feminist teachers was the persistence and vigour with which they pursued their specific interests as working women--to the extent that their commitment to equal pay, women's suffrage and equal opportunities split the NUT along gender lines in 1919-1920 and led to thousands of them setting up the NUWT as a specifically feminist trade union. The author discusses why this particular group of women workers was so strongly politicised as feminists and formulates her analysis of why so many women teachers came to have such a strong sense of selfhood, entitlement, and agency which fuelled their political activism. (Contains 8 notes.)