Sorcha MacMahon was an early member of Cumann na mBan, being active as the national secretary in 1916. Extremely efficient, she took on duties of training women in first aid and home nursing. It was also her responsibility to find reliable ladies who supported the 1916 cause, and who were willing to deliver messages in those days leading up to the Rising, which included some traveling on her part.
When the Rising did occur on Easter Monday, it fell onto Sorcha to deliver mobilization orders to the Central Branch Cumann na mBan section leaders. She carried messages and guns which were hidden in her bicycle basket. Throughout the entire week, she continued to distribute messages from the GPO, ignoring the dangers she faced. Records show that she left the GPO for various locations over 50 times that week.
Sorcha was never charged by the British for crimes committed during the Rising. Later, during the War of Independence, Sorcha worked directly for Michael Collins. When the Cumann na mBan announced they were anti-treaty, she resigned the group to continue Collin’s work until his death in 1922.