Soon after their accession, William and Mary rewarded Churchill by granting him the Earldom of Marlborough. Their subsequent treatment of the Marlboroughs, however, was not as favourable. In 1692, suspecting that
Lord Marlborough was a
Jacobite, Mary dismissed him from all his offices. Lady Marlborough was subsequently removed from the Royal Household, leading Princess Anne to angrily leave her royal residence for
Syon House, the Duke of Northumberland's home. Princess Anne was then stripped of her guard of honour, and the guards at the royal palaces were forbidden to salute her husband.
When Mary II died of
smallpox in 1694, William III continued to reign alone. Anne then became his
heir apparent, since any children he might have by another wife were assigned to a lower place in the line of succession. Seeking to improve his own popularity (which had always been much lower than that of his wife), he restored Princess Anne to her previous honours, allowing her to reside in
St. James's Palace. At the same time William kept her in the background and refrained from appointing her regent during his absence.
In 1695, William sought to win Princess Anne's favour by restoring Marlborough to all of his offices. In return Anne gave her support to William's government, though about this time, in 1696 — according to James, in consequence of the near prospect of the throne — she wrote to her father asking for his leave to wear the crown at William's death, and promising its restoration at a convenient opportunity. The unfounded rumour that William contemplated settling the succession after his death on James's son, provided he were educated a Protestant in England, may possibly have alarmed her.