William III of England. William III, also widely known as William of Orange, was sovereign Prince of Orange from birth, Stadtholder of Holland, Zeeland, Utrecht, Guelders and Overijssel in the Dutch Republic from the 1670s and King of England, Ireland and Scotland from 1689 until his death, co-reigning with his wife, Queen Mary II. Popular histories usually refer to their joint reign as that of William and Mary.
As King of Scotland, he is known as William II. He is sometimes informally known as King Billy in Northern Ireland and Scotland, where his victory at the Battle of the Boyne in 1690 is still commemorated by Unionists and Ulster loyalists. William was the only child of William II, Prince of Orange, who died a week before his birth, and Mary, Princess of Orange, the daughter of King Charles I of England.
In 1677, during the reign of his uncle King Charles II of England, he married his cousin Mary, the fifteen-year-old daughter of Charles II's brother James, Duke of York. A Protestant, William participated in several wars against the powerful Catholic King Louis XIV of France, in coalition with Protestant and Catholic powers in Europe.
Many Protestants heralded him as a champion of their faith. In 1685, his Catholic uncle and father-in-law, James, became King of England, Scotland and Ireland.
James's reign was unpopular with the Protestant majority in Britain, who feared a revival of Catholicism.