He was born in Grimsthorpe, the second son of the General Peregrine Bertie, 3rd Duke of Ancaster and Kesteven (died 1778), and Mary Panton (died 1793) On the death of his elder brother, Peregrine Thomas Bertie, Marquess of Lindsey, on 12 December 1758, he inherited the courtesy title of Marquess of Lindsey.

[2] On his father's death on 12 August 1778, he succeeded as 4th Duke of Ancaster and Kesteven, 4th Marquess of Lindsey, 7th Earl of Lindsey, 20th Baron Willoughby de Eresby and Hereditary Lord Great Chamberlain.

On 12 February 1779 he was invested as Privy Counsellor and was Lord Lieutenant of Lincolnshire.

On his death, the Hereditary Lord Great Chamberlainship and the Barony Willoughby de Eresby fell into abeyance between his two sisters, all other titles of his passed to his uncle.

An illegitimate daughter of the 4th duke, Susan, was married to Banastre Tarleton; but there were no children.