Maureen Paula O’Sullivan was the daughter of Mary (née Frazer) and Charles Joseph O’Sullivan, an officer in the Connaught Rangers who served in World War I. She attended a convent school in Dublin, then the Convent of the Sacred Heart at Roehampton (now Woldingham School), England. One of her classmates there was Vivian Mary Hartley, future Academy Award-winning actress Vivien Leigh. After attending finishing school in France, O’Sullivan returned to Dublin to work with the poor.

Maureen O’Sullivan was discovered by director Frank Borzage and her first screen success came in 1931 with Will Rogers in A Connecticut Yankee. Her most famous role was Jane in the Tarzan series, opposite Johhny Weissmuller. O’Sullivan had seven children (including Mia Farrow) with husband John Farrow. She died in 1998.