Maria Clementina Sobieska (18 July 1702 –18 January 1735) was a Polish noblewoman, the granddaughter of the Polish king John III Sobieski.
She was born on 18 July 1702 in Ohlau, Silesia, Holy Roman Empire. Her parents were James Louis Sobieski (1667–1737), the eldest son of King John III, and Countess Palatine Hedwig Elisabeth of Neuburg (1673–1722). Her older sister Maria Karolina (known as Charlotte) was the Duchess of Bouillon by marriage.
Being one of Europe's wealthiest heiresses, she was betrothed to James Francis Edward Stuart. King George I of Great Britain was opposed to the marriage because he feared that the union might produce heirs to James Francis Edward's claim to his thrones. To placate him, the Holy Roman Emperor Charles VI arrested Maria Clementina while on her way to Italy to marry James Francis Edward. She was confined in Innsbruck Castle but eventually the guards were deceived and Maria Clementina escaped to Bologna, Italy, where, for safety from further intrusions, she was married by proxy to James who was in Spain at that time.
Maria Clementina's father, James Louis Sobieski, approved her escape declaring that, as she became engaged to James Francis Edward she ought to "follow his fortune and his cause".
Maria Clementina and James Francis Edward were formally married on 3 September 1719 in the Chapel of episcopal palace of Montefiascone, Italy in the Cathedral of Santa Margherita. Following their marriage, James and Maria Clementina were invited to reside in Rome at the special request of Pope Clement XI, who acknowledged them as the King and Queen of England, Scotland and Ireland.
The Pope provided them with a papal guard of troops, gave them the Palazzo Muti in the Piazza dei Santi Apostoli in Rome to live in, plus a country villa at Albano. The Catholic Church also provided them with an annual allowance of 12,000 crowns out of the papal treasury. The Popes Clement XI and Innocent XIII considered James and Maria Clementina the rightful and, more importantly, Catholic King and Queen of England, Scotland and Ireland: the cousin of Pope Innocent XIII, Francesco Maria Conti, from Siena, was here the Gentiluomo di Camera (the chamberlaine) in the little Roman Jacobite court.
The married life of James and Maria Clementina proved turbulent and unhappy. Soon after their second child's birth, Maria Clementina left him and went to live in Rome in the convent of St. Cecilia. She accused her husband of adultery and he said it was sinful to leave him and her children. It was more than two years before they reconciled. Maria Clementina was prone to depression, spending much of her time praying.
Maria Clementina died at the early age of 32 on 18 January 1735. She was interred with full royal honors in St. Peter's Basilica in Rome. Pope Clement XII ordered that she have a state burial. Pope Benedict XIV commissioned Pietro Bracci (1700–1773) to sculpt a monument to her memory, which was erected in the Basilica.
Maria Clementina and James Francis Edward had two sons:
Charles Edward Louis Philip Casimir Stuart (1720–1788), aka "Bonnie Prince Charlie", married Louise of Stolberg-Gedern and had no issue; had affair with his cousin Marie Louise de La Tour d'Auvergne and had issue; had issue with his mistress Clementina Walkinshaw;
Henry Benedict Maria Clement Thomas Francis Xavier Stuart (11 March 1725 – 13 July 1807), later known as the Cardinal Duke of York, never married.