Lady Greville died in childbirth at the age of 19. On 14 July 1776, Greville married Henrietta Vernon, the daughter of Hon. Richard Vernon and Lady Evelyn Leveson-Gower, at the house of her uncle Earl Gower in Whitehall. They had four children:
On 6 July 1773, Greville inherited his father's title of Earl of Warwick and left the House of Commons. He also left office on the Board of Trade in 1774, although he served as recorder of Warwick from 1773 to 1816. He became a colonel in the Warwickshire Fencibles in 1795, and was appointed Lord Lieutenant of Warwickshire in that year, which office he held until his death on 2 May 1816 in London. He was buried at Warwick on 12 May 1816. The Lives of Celebrated Persons records that "the latter part of the Earl's life was in penury, mortification and wretchedness." The Biographical Index to the House of Lords records that "this peer has evinced a predominant taste for chymistry, and if we mistake not greatly, a patent for soap for the navy that will not curdle in salt water was taken out in his name."
Collector and Patron
George Greville was arguably one of the greatest contributors to the Greville Collection at Warwick Castle. His greatest purchase was the infamous Warwick Vase, acquired from his Uncle Sir William Hamilton by 1778. Although he furnished the Castle with several works from Classical Antiquity, his principle interest was in portraits. He amassed in his own words a "matchless collection of pictures by Sir Peter Paul Rubens and Sir Anthony Van Dyck", several of which are still in the collection at Warwick Castle. The first in-depth inventory of pictures dates from 1809, and records the wide range of pictures amassed by the Earl. However, it is still unclear which paintings were already in his father's collection, and exactly where he sourced the major works from. He was patron to John Higton, it being thought that he was introduced to Higton by his brother Charles Francis Greville, the friend of Higton's patron Lord Sedley. However, it has only recently been understood that Greville's wife, Henrietta Vernon, was the half sister of John FitzPatrick, Lord Gowran via the first Marriage of her Mother, and a cousin of Lord Sedley via her father Richard Vernon. Therefore, Higton's portraits of Warwick Castle, combined with those of Dogs belonging to George Greville, Lord Sedley, and John Fitzpatrick, perhaps reflect a more intimate relationship with the family, and their circle, than was understood. He was also the first aristocratic patron to George Romney, from whom he commissioned several portraits of his children and two wives. He was most likely to have been introduced to Romney through Richard Cumberland, and both probably encouraged him to depart on his travels to Italy in 1772. Although Greville had commissioned Romney to purchase paintings on his behalf in Italy, lack of pictures of quality meant that he returned empty handed. His brother Charles Francis Greville also sat to Romney, and introduced the artist to the muse Emma Hamilton. The offer of a studio in one of the towers of Warwick Castle was later turned down by the artist, who wished to remain in London.
