His grandson William Fitzwilliam (d. 1643) was raised to the Peerage of Ireland as
Lord Fitzwilliam, Baron of Liffer, alias
Lifford, in the
County of Donegal, in 1620. He was the first Baron FitzWilliam. His son was
William FitzWilliam, 2nd Baron FitzWilliam (c.1609 – 21 February 1658). His son William became 3rd Baron FitzWilliam.
Earl Fitzwilliam of Fitzwilliam:
Lozengy argent and gules The 3rd Baron FitzWilliam succeeded his father in 1658, and in 1716 was created the first
Earl Fitzwilliam, of the County of Tyrone with the subsidiary title
Viscount Milton, in the County of Westmeath, also in the Peerage of Ireland. The eldest son of the Earl Fitzwilliam bore the
courtesy title Viscount Milton. He was succeeded by his son, the second Earl. The second Earl,
John Fitzwilliam, sat as member of parliament for
Peterborough. On his death, the titles passed to his son, the third Earl. The third Earl,
William Fitzwilliam, also represented Peterborough in the
House of Commons. In April 1742 he was created
Lord Fitzwilliam, Baron of Milton in the County of Northampton, in the Peerage of Great Britain, and in 1746 he was further honoured when he was made
Earl Fitzwilliam, of Norborough with the subsidiary title
Viscount Milton, both in the County of Northampton, also in the Peerage of Great Britain. Lord Fitzwilliam married Lady Anne Watson-Wentworth (died 1769), daughter of
Thomas Watson-Wentworth, 1st Marquess of Rockingham, and sister of
Charles Watson-Wentworth, 2nd Marquess of Rockingham. He was succeeded by his son, the fourth Earl. The fourth Earl,
William Fitzwilliam, was a prominent
Whig politician and served as
Lord President of the Council and as
Lord-Lieutenant of Ireland. In 1782 he inherited the Watson-Wentworth estates (including
Wentworth Woodhouse) on the death of his uncle Lord Rockingham, which made him one of the greatest landowners in the country. When he died the titles passed to his son, the fifth Earl. The fifth Earl,
Charles Wentworth-Fitzwilliam, represented several constituencies in the House of Commons and was made a
Knight of the Garter in 1851. In 1856 Lord Fitzwilliam assumed by Royal licence the additional surname of Wentworth. He was succeeded by his second but eldest surviving son, the sixth Earl. The sixth Earl was
William Wentworth-Fitzwilliam. He sat as member of parliament for
Malton and
County Wicklow and served as
Lord Lieutenant of the West Riding of Yorkshire. His eldest son
William FitzWilliam, Viscount Milton, was also a member of parliament but predeceased his father. Lord Fitzwilliam was therefore succeeded by his grandson, the seventh Earl. Also,
Lady Mabel Fitzwilliam, a socialist politician and "an ardent pioneer in education and social welfare", was a granddaughter of the 6th Earl. The seventh Earl was
William Wentworth-Fitzwilliam (25 July 1872 – 15 February 1943), the eldest son of Viscount Milton (William Wentworth Fitzwilliam). He represented
Wakefield in Parliament as a
Liberal Unionist. When he died the titles passed to his son, the eighth Earl. The eighth Earl was
Peter Wentworth-Fitzwilliam (31 December 1910 – 13 May 1948). He was killed in an air crash in France. On his early death the line of the eldest son of the sixth Earl failed and titles passed to the late Earl's first cousin once removed, the ninth Earl. The ninth Earl was
Eric Spencer Wentworth-Fitzwilliam (4 December 1883 – 3 April 1952). He was the son of Captain the Hon. Sir William Charles Wentworth-Fitzwilliam, fourth son of the sixth Earl. When he died in 1952 this line of the family also failed and the titles were inherited by his second cousin, the tenth Earl. The tenth Earl was
William Thomas George Wentworth-Fitzwilliam (28 May 1904 – 21 September 1979). He was the son of George Charles Wentworth-Fitzwilliam, son of the Hon.
George Wentworth-FitzWilliam, MP, third son of the fifth Earl. He and his wife had no children. ==After extinction==