In November 1929, a census taker named Mark Emeruwa entered the compound of a woman named Nwanyeruwa in the village of Oloko. He was there to count her livestock and family members—a prelude to taxing women, a practice previously unheard of in Igbo society. Nwanyeruwa refused, telling him: "Was your mother counted?" A physical confrontation ensued, and Nwanyeruwa ran to the village square to tell the market women what had happened.

This incident sparked what the British colonial administration called the 'Aba Riots,' but what the Igbo people remember as the **Ogu Umunwanyi**—the Women's War. Within days, thousands of women from across eastern Nigeria mobilized using traditional networks of communication, such as palm leaves sent from village to village.

The women converged on colonial administration offices in Aba, Owerri, and Calabar. They practiced 'sitting on' warrant chiefs—a traditional Igbo form of public shaming where women gathered outside a man’s house, sang satirical songs, danced, and sometimes dismantled his compound until he repented. They demanded the resignation of the warrant chiefs, who were seen as corrupt instruments of British indirect rule.

The British response was swift and brutal, opening fire on protesters in some locations. Despite the loss of lives, the women’s courage forced the colonial office to abandon plans to tax women, reform the warrant chief system, and include women in native court appointments, demonstrating the formidable power of organized female authority in pre-colonial and colonial Nigeria.