Mary II (30 April 1662 – 28 December 1694) is joint Sovereign of England, Scotland, and Ireland with her husband and first cousin, William III and II, from 1689 until her death.

William and Mary, both Protestants, become king and queen regnant, respectively, following the Glorious Revolution, which results in the deposition of her Roman Catholic father, James II and VII.

William becoms sole ruler upon her death in 1694.

Popular histories usually refer to their joint reign as that of "William and Mary".

Mary wields less power than William when he is in England, ceding most of her authority to him, though he heavily relies on her.

She does, however, act alone when William is engaged in military campaigns abroad, proving herself to be a powerful, firm, and effective ruler.