Background
Bertie was the son of Robert Bertie, 3rd Earl of Lindsey and Elizabeth Wharton.
Bertie was the son of Robert Bertie, 3rd Earl of Lindsey and Elizabeth Wharton.
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 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 Willoughby married Mary Wynn (d 20 September 1689), a Welsh heiress, daughter of Sir Richard Wynn, 4th Baronet and direct descendent of the princely house of Aberffraw.
They had five children: Robert Bertie, Lord Willoughby (6 February 1683 – 4 May 1704), died while studying at the Wolfenbüttel Ritter-Akademie Peregrine Bertie, 2nd Duke of Ancaster and Kesteven (1686–1742) Lady Elizabeth, Lady Eleanor, and Lady Mary Bertie, who died unmarried. William Farington, by whom he had: Lord Vere Bertie (d 1768) Lord Thomas Bertie (24 July 1720 – 21 July 1749) Lieutenant-General
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. His widow remarried to James Douglas and died in 1745.
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).