Mary MacSwiney (Máire Nic Suibhne) was born in London to an Irish father and English mother. The family returned to Cork when she was six and she was educated at St. Angela’s Ursuline convent school. She obtained a teaching diploma at Cambridge University and taught at schools in England before returning to Cork on the death of her mother in 1904 to care for younger members of the family. She took up a teaching post in St. Angela’s.
Mary MacSwiney attended the first meeting of the Munster Women’s Franchise League and became a committee member. She also joined the Gaelic League and Inghinidhe na hÉireann. She was a founder member of Cumann na mBan in Cork in 1914 and became a national vice-president of the organisation. She was arrested and imprisoned after the Easter Rising and dismissed from her job at the Ursuline.
Upon her release from prison, Mary MacSwiney established, along with her sister Annie, Scoil Íte, which was influenced by Patrick Pearse’s St. Enda’s. Her brother Terence, Sinn Féin Lord Mayor of Cork, died on hunger strike in October 1920. Along with another brother, Seán, in another Cork constituency, she was elected to the Dáil in 1921. She went to Washington to give evidence before the American Commission on conditions in Ireland. She conducted a tour of America with Terence’s widow, Muriel (Murphy), and was the first woman to be granted the freedom of New York City. She virulently opposed the Anglo-Irish Treaty and was interned during and after the Civil War, twice going on hunger strike. Annie MacSwiney also went on hunger strike. Mary retained her seat at the 1923 general election but, as per Sinn Féin policy, refused to enter the Dáil.