In Dec 1800 King George III of Great Britain and Ireland (age 62) created a number of peers who supported the Act of Union ....

On 21 Dec 1800 Charles Stanley Monck 1st Viscount Monck (age 46) was created 1st Viscount Monck.

On 29 Dec 1800 ....

Murrough O'Brien 1st Marquess Thomond (age 74) was created 1st Marquess Thomond. Mary Palmer Marchioness Thomond (age 50) by marriage Marchioness Thomond.

Charles Tottenham aka Loftus 1st Marquess Ely (age 62) was created 1st Marquess Ely in County Wexford. Jane Myhill Marchioness Ely by marriage Marchioness Ely in County Wexford.

James Alexander 1st Earl Caledon (age 70) was created 1st Earl Caledon in County Tyrone.

The London Gazette 15317. Whitehall, December 9, 1800.

The King has been pleased to grant the Dignities of Viscount and Earl of the Kingdom of Great Britain to the Right Honorable Charles Sloane Lord Cadogan (age 72), and the Heirs Male of his Body lawfully begotten, by the Name, Style, and Title of Viscount Chelsea, in the County of Middlesex, and Earl Cadogan. [Mary Churchill Countess Cadogan (age 42) by marriage Countess Cadogan.]

The King has also been pleased to grant the Dignities of Viscount and Earl of the Kingdom of Great Britain to the Right Honorable James Lord Malmesbury (age 54), Baron of Malmesbury, in the County of Wilts, Knight of the Most Honorable Order of the Bath, and the Heirs Male of his Body lawfully begotten, by the Name, Style, and Title of Viscount Fitz-Harris, of Hurn Court, in the County of Southampton, and Earl of Malmesbury. [Harriet Maria Amyand Countess Malmesbury (age 39) by marriage Countess Malmesbury.]