Born in England, Mary and her mother survived on a pension from James VI and I and she grew up in Ireland as a Catholic.
Due to her strong-willed nature and devout Catholicism, she became estranged from her mother's Protestant family, and after breaking into a London prison to free Irish fugitives, she fled to Brussels with her boyfriend Dualtach O'Gallagher.
Rory was forced to renounce claims of land, and was bitterly discontented with his newfound financial difficulties and reduced status.
[2] Due to increasing hostility from the English government,[6][4] Rory fled Ireland in September 1607 whilst Bridget was pregnant with their second child.
[3][7] It was apparently a "snap decision",[8] and as Bridget was staying at her paternal grandmother's Maynooth estate at the time, far away from the point of departure in Rathmullan, she was left behind.
[17] Lady Kildare attempted to anglicise the young girl and proposed to leave Mary her substantial inheritance.
[17] In the summer of 1626,[17] Mary and several friends broke into a London prison[a] and freed her half-brother Caffar "Con" O'Donnell and her first cousin Hugh O'Rourke,[17][19] who had recently been incarcerated for refusing to revoke their claims over planted land in Ireland.
[17] Disguised as a man[15][20] named Rudolph Huntley,[21] and wearing a sword, she got clear of London and after many wanderings arrived in Bristol.
She was accompanied by a maid,[15] Anne Baynham,[citation needed] similarly disguised, and by a young "gentilhomme son parent" (most likely O'Gallagher).
[15] At Bristol her sex was suspected; but, according to a Spanish panegyrist, who likens her to various saints, she bribed a magistrate, offered to fight a duel, and made fierce love to another girl.
Enriquez does not mention O'Gallagher's presence - the fact that Mary was travelling with a man of lower status was seen by some as a reason for scandal.
[citation needed] On her arrival at Brussels in January 1627,[17] Pope Urban VIII wrote her a special congratulatory letter.
[17] However, Mary faced difficulties with her new compatriots when Archbishop of Tuam Florence Conry arranged for her to be married to Shane O'Neill, 3rd Earl of Tyrone,[17] an Irish nobleman who had become a decorated officer in the Spanish army.
[23] The relations between the O'Neills and the O'Donnells had become strained after the war's end, and Conry hoped a unifying marriage would allay hostilities between the noble families.
She secretly wrote to Lord Conway, English Secretary of State, defending her flight from authorities, and proposing that with the right guarantee, she could return to England, and with her, bring Shane into the King's service.
[17] In February 1632 Mary wrote to Cardinal Barberini (nephew of Pope Urban VIII) saying that another child was expected.
[citation needed] Beset by grief and estranged from her family, she travelled Europe once again before eventually settling down in Rome.