Simplify the following text for a Grade 8 native English-speaking person.
Original: From 11 April 1689 â '' when the Estates of Scotland recognized them as Sovereignsâ '' the royal couple used the style `` William and Mary , by the Grace of God , King and Queen of England , Scotland , France and Ireland , Defenders of the Faith , etc. '' .
Simplified: On 11 April 1689 , the Estates of Scotland recognized them as Sovereigns . From then on , William and Mary called themselves `` William and Mary , by the Grace of God , King and Queen of England , Scotland , France and Ireland , Defenders of the Faith , etc. '' .