Mary Beatrice d'Este was educated in a convent, where she been taught to be a submissive, good, and devout wife. Despite this upbringing, she herself hoped to become a nun A hope that was thwarted when her father, Duke Alfonso of Modena, agreed to Louis XIV.'s suggestion and in 1673 proposed her as a candidate for the second marriage of the recently-widowed James, Duke of York. From Louis's viewpoint it was a good move - Mary of Modena would bring a stronger Catholic influence on the heir to the English throne as well as encourage a pro-French attitude . From James's viewpoint it was arrant stupidity: to marry a vehemently Catholic Princess in the year of the Test Act it would make him even less popular than he was already.

But marry her he did, and brought the wrath of an angry Parliament and county down on his own, and his brother, the Kings head. Mary herself soon found favour at court, and was on good terms with her stepdaughters - particularly Mary, who was only two years her junior. But she was never popular in the country, where she soon acquired a reputation for haughtiness - not surprising in a fifteen-year-old girl struggling both for dignity and to master a foreign language.

At first Mary was indeed a submissive and amiable wife: James was twenty-five years older and his amours were almost as notorious as Charles II's; between 1675 and 1682 she bore five children, all of whom died soon after birth; but during this time she followed James on his travels uncomplainingly. Following the scandal of the Popish Plot ( in which her secretary was fatally involved ), and the Test Act of 1679, James went first to the Netherlands and then to Scotland. Though he returned to England the next year, he went hack to Scotland again almost at once, where he remained for two years.

By the time the pair were installed in London once more, Mary was considerably more mature and self-assured. Her deep Catholic piety was a constant encouragement to James, and when he became King , in 1685 she readily identified herself with the aggressively Catholic faction. In her new position as Queen she found James's continuing infidelities increasingly distressing, and gave way more often to outbursts of fierce anger. Her scenes, and the influence of her confessor, forced James to give up his favourite mistress, Catherine Sedley, who was the Protestants' main hope of influence over the King. The Queen was beginning to show her true colours.

Early in November 1687 Mary announced her pregnancy possibly no-one was more astonished than herself, for everyone had given up hope that she would bear an heir to the throne. Catholics throughout the country prayed ardently for a son, while extreme Protestants began to spread rumours that the Queen was not really pregnant at all. The birth of the child on June 10. 1688, took place, as usual, with a host of witnesses. But James and Mary made a serious error: there was not one notable Protestant witness present who would be believed by the country at large. Immediately rumours of a baby smuggled into Mary's bed in a warming-pan began to circulate, and no amount of protestation by court circles could scotch the notion. Prince James Francis Edward - the " Old Pretender " - would never be free of this scurrilous tale surrounding his birth.

From now on events moved fast. Prince William, of Orange sailed for England at the end of October and Protestants flocked to his standard. James, deserted by his children and most of his army, fell back on his wife's and the priests advice. On December 10 Mary sailed for France with her son, and James, after an abortive attempt the next day, followed her on December 23. The rest of their lives were spent in exile.

Though Mary had often opposed the French influence at the English court, she now set herself to gain Louis XIV's support. Her gracious manner soon made a favourable impression and her ardent Catholicism was much admired; unfortunately James rapidly came to be despised for his weakness and vacillation, and it was obvious by this time that Mary was the dominant character of the two. She encouraged all kinds of schemes for the invasion of England, and was particularly in favour of a religious war, but none of her plans came to fruition.

The pair lived on the charity of Louis at St. Germain, and Mary made frequent retreats to the convent at Chaillot. Their daughter Princess Louisa was born in 1692. Following James's death in 1701 Louis gave Mary an annuity of a hundred thousand francs, so much did he admire her personally and value her worth politically. In the seventeen years left to her after the death of James, Mary turned more and more to her religion and became increasingly devout. Praised for her dignity and devotion by St. Simon and Madame de Sevigne, she remained an object of admiration in France to the end of her life - and bitterly unpopular in England.