Mary was the eldest daughter of James, Duke of York (who succeeded as James II in 1685) and his first wife Anne Hyde (1637-1671). She was born at St James's Palace on 30th April 1662.
She was married, aged 15, to her cousin William, Prince of Orange. For many years they lived in Holland but when the Catholic James II had a son the English authorities called on William to come to England to safeguard the Protestant succession and rule jointly with Mary. Before William reached London James had fled to France. They had no children. Her sister Anne succeeded to the throne on the death of William III.
William III and Mary II were crowned as joint monarchs in the Abbey on 11th April 1689. The king was crowned in the ancient Coronation Chair so a new chair had to be specially made for Mary's use and this is now in the Abbey collection.
Watch: William III and Mary II and the wrong ring
She died of smallpox on 28th December 1694. Her magnificent funeral on 5th March 1695 cost £50,000. She lay in state in the Banqueting House in Whitehall and the choir sang during the procession to the Abbey. The music Henry Purcell composed for the occasion was used at his own funeral a year later. William III did not attend but both Houses of Parliament were there. She lies buried in a vault in the south aisle of Henry VII's chapel, not far from her mother Anne. A monument to her memory was designed but never erected, probably due to lack of space in the chapel. Only a small stone marks her grave.
In 1725 the Abbey acquired life-size wax effigies of the two monarchs, possibly made by Mrs Goldsmith. That of William is a remarkable likeness. Mary was larger and taller (5 feet 11 inches) than her husband (5 feet 6½ inches) and his effigy stands on a cushion beside hers. Underneath her brocaded silk petticoat is a brown leather one with Baroque patterns and Chinese figures painted in gold. A crown is placed between them to signify they were joint monarchs.
The wax effigies and Mary's chair are on display in the new Queen's Diamond Jubilee Galleries
William and Mary by H. & B. van der Zee, 1973
The funeral effigies of Westminster Abbey edited by A. Harvey & R. Mortimer, revised 2003
The form and proceeding to the funeral of...Queen Mary II, 1695
British Royal and State funerals...by M. Range, 2016
Romeyn de Hooghe and the funeral of the People's Queen by Ralph Hyde, in Print Quarterly XV, 1998
Oxford Dictionary of National Biography, 2004
Papers concerning the funeral are in The National Archives
[Public domain] via Wikimedia Commons