Thomas de Grey, 2nd Earl de Grey

Detail from a silver gilt dish made in 1802 for the 3rd Baron Grantham by Robert Garrard of London, showing the engraved arms of Robinson quartering Weddell

He was the eldest son of Thomas Robinson, 2nd Baron Grantham (1738–1786) of Newby Hall, Newby-on-Swale, a deserted medieval village and of adjacent Rainton, both in the parish of Topcliffe in Yorkshire,[2] by his wife Mary Yorke (1757–1830), the younger daughter of Philip Yorke, 2nd Earl of Hardwicke by his wife Jemima Campbell, suo jure 2nd Marchioness Grey. His younger brother was the Prime Minister Frederick John Robinson, 1st Earl of Ripon, 1st Viscount Goderich, known to history as "Lord Goderich".

In 1786 he succeeded his father as 3rd Baron Grantham. In 1792 he became the heir of his distant cousin[3] William Weddell (1736–1792) of Newby Hall in Yorkshire, a notable art collector. Also in 1792 he became the 6th Robinson Baronet "of Newby", succeeding his father's first cousin Norton Robinson, 5th Baronet (died 1792).[4] In 1833 he succeeded his maternal aunt Amabel Hume-Campbell, suo jure 1st Countess de Grey and 5th Baroness Lucas (1750–1833), as 2nd Earl de Grey (according to a special remainder) and as 6th Baron Lucas, of Crudwell. He also inherited her estate of Wrest Park in Silsoe, Bedfordshire.

In 1798 he was admitted to St John's College, Cambridge, graduating MA in 1801.[5] He was made Privy Counsellor in December 1834 while holding office as First Lord of the Admiralty till April 1835, and a Knight of the Garter in 1844. He was colonel-commandant of the Yorkshire Hussars, a part-time Yeomanry Cavalry regiment, for over forty years and was appointed yeomanry aide-de-camp to William IV and held similar position under Queen Victoria. Lord Grantham was nominated as Lord Lieutenant of Bedfordshire in 1818, an office which he held until his death. He served as Lord Lieutenant of Ireland from September 1841 to July 1844. During his time in Ireland he disagreed with Peel's religious conciliation of Ireland, claiming that economic conciliation was a greater priority.[6] He called for more legislation focused on Ireland whilst Peel pursued economic legislation aimed at benefitting the UK as a whole.[6]

In 1805 he married Lady Henrietta Cole, a daughter of William Cole, 1st Earl of Enniskillen, by whom he had two daughters and co-heiresses:

• Ann Florence de Grey (Countess Cowper), eldest daughter and co-heiress, who married George Cowper, 6th Earl Cowper. She was suo jure Baroness Lucas, having inherited that title from her father.
• Mary Gertrude de Grey, younger daughter and co-heiress.

Lord de Grey died in November 1859, aged 77, having survived his wife by eleven years. He was succeeded in the Barony of Lucas of Crudwell by his daughter, Ann de Grey (Countess Cowper), who married George Cowper, 6th Earl Cowper. His other titles, unable to pass via a female line, passed to his heir male, namely his nephew, George Robinson, 1st Marquess of Ripon, 2nd Earl of Ripon.

• The Earl de Grey's account of the building of Wrest House, History of Wrest House, introduction by A. F. Cirket, The Bedfordshire Historical Record Society, Volume 59, pp 65–87, Bedford 1980
• Earl de Grey, Charles Read, London 2007

• Thomas Philip de Grey, 2nd Earl de Grey | National Portrait Gallery
• Thomas Philip de Grey | National Trust Art