Robert Bertie, 1st Duke of Ancaster and Kesteven
Robert Bertie, 1st Duke of Ancaster and Kesteven PC (20 October 1660 – 26 July 1723), styled Lord Willoughby de Eresby between 1666 and 1701 and known as The Earl of Lindsey between 1701 and 1706 and as The Marquess of Lindsey between 1706 and 1715, was a British statesman and nobleman.
Bertie was the son of Robert Bertie, 3rd Earl of Lindsey and Elizabeth Wharton.
Political career 
Lord Willoughby entered Parliament as Member of Parliament for Boston in 1685, and sat in the Loyal Parliament (1685–1687) and the Convention Parliament (1689–1690). In 1690, he was returned for Preston instead, but was soon forced to leave the House of Commons for the House of Lords after receiving a writ of acceleration as Baron Willoughby de Eresby. He served as Chancellor of the Duchy of Lancaster from 1689 until 1697.
Lord Willougby inherited the earldom of Lindsey in 1701, and was invested a Privy Counsellor one month later; along with the Earldom of Lindsey, he also inherited the offices of Lord Great Chamberlain and Lord Lieutenant of Lincolnshire, both of which he would hold until his death and would pass onto his son, the 2nd Duke of Ancaster and Kesteven. Lord Lindsey, as he was now styled, was then created Marquess of Lindsey in 1706, and was finally created Duke of Ancaster and Kesteven in 1715 (that year, he also served temporarily as a Lord Justice).
On 30 July 1678, Lord Willougby married Mary Wynn (d. 20 September 1689), a Welsh heiress and direct descendent of the princely house of Aberffraw. They had five children:
Robert Bertie (b. 6 February 1683, c. 14 Feb 1683 St Martin In The Fields, Westminster, London, Middlesex, England d. young)
Peregrine Bertie, 2nd Duke of Ancaster and Kesteven (1686–1742),
and three daughters, Elizabeth, Eleanor, and Mary, who died unmarried.
After the death of his first wife in 1689, he married Albinia Farington, daughter of Maj.-Gen. William Farington, by whom he had:
- Lord Vere Bertie (d. 1768)
- Capt. Lord Montagu Bertie (d. 12 December 1753), married Elizabeth Piers (d. 1782), daughter of William Piers
- Capt. Lord Thomas Bertie (24 July 1720 – 21 July 1749)
- Lt.-Gen. Lord Robert Bertie (1721–1782)
- Lady Louisa Bertie, married Thomas Bludworth in 1736
Ancaster died in July 1723, aged 62, an established but relatively unheralded statesman.
- "Bertie genealogy". Retrieved 2007-09-05.