This study discusses the life and political struggles of Josie Mpama (1903–1979), a leader in the resistance against colonial oppression and the apartheid system in South Africa. Josie was a key figure in the history of women organisers in South Africa and a leader in the Communist Party of South Africa. Her life teaches us about the importance of grassroots and mass organising, as well as the challenges that come with that work. Like so many women involved in radical politics, particularly in the Global South, Josie’s extraordinary political contributions and theoretical acumen have been overlooked and largely excluded from the mainstream historical record.