Background
He was born John Brudenell, eldest son of George Brudenell, 4th Earl of Cardigan by his wife Mary, daughter of John Montagu, 2nd Duke of Montagu.
He was born John Brudenell, eldest son of George Brudenell, 4th Earl of Cardigan by his wife Mary, daughter of John Montagu, 2nd Duke of Montagu.
As heir-apparent to the Earldom of Cardigan he was styled Lord Brudenell from birth. One of the Montagu family titles was revived in the person of Lord Brudenell when he was created Baron Montagu, of Boughton in the county of Northampton, on 8 May 1762. In 1764 his portrait was painted by Pompeo Batoni.
Lord Monthermer died on 11 April 1770 at the age of thirty-five.