William III (Dutch: Willem; 4 November 1650 – 8 March 1702), 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.