William III and Mary II are crowned as joint sovereigns of Great Britain on the same day that the Scottish Parliament concurs with the English decision of 12 February.

William III, also known as William of Orange, was the sovereign Prince of Orange from birth, Stadtholder of Holland, Zeeland, Utrecht, Guelders, and Overijssel in the Dutch Republic from 1672, and King of England, Ireland, and Scotland from 1689 until his death in 1702. He ruled Great Britain and Ireland with his wife, Queen Mary II, and their joint reign is known as that of William and Mary.

Mary II was Queen of England, Scotland, and Ireland with her husband, King William III and II, from 1689 until her death in 1694. She was also Princess of Orange following her marriage on 4 November 1677. Her joint reign with William over Britain is known as that of William and Mary.

April 11 is the 101st day of the year in the Gregorian calendar; 264 days remain until the end of the year.