In 1644 Prince Rupert Palatinate Simmern 1st Duke Cumberland (age 24) was created 1st Duke Cumberland, 1st Earl Holderness by King Charles I of England, Scotland and Ireland (age 43).

In 1689 Prince George of Denmark 1st Duke Cumberland (age 35) was created 1st Duke Cumberland by his father-in-law King James II of England Scotland and Ireland (age 55). Queen Anne of England Scotland and Ireland (age 23) by marriage Duchess Cumberland.

The London Gazette 6494. Whitehall, July 15 [1726].

His Majesty has been pleased to create his Highness Prince Frederick (age 19), a Baron, Viscount, Earl, Marquess, and Duke of the Kingdom of Great Britain, by the Names Stiles and Titles of Baron of Snaudon in the County of Caernarvon, Viscount of Lanceston in the County of Cornwall, Earl of Eltham in the County of Kent, Marquess of the Isle of Wight [Note. An error for Isle of Ely], and Duke of Edinburgh.

His Majesty has been pleased to create his Highness Prince William (age 5), a Baron, Viscount, Earl, Marquess, and Duke of the Kingdom of Great Britain, by the Names Stiles and Titles of Baron of the lsle of Alderney, Viscount of Trematon in the Councy of Cornwall, Earl of Kinnington in the County of Surrey, Marquess of Berkhamstead in the County of Hertford, and Duke of Cumberland.