Wilhelmina Powlett, Duchess Of Cleveland

Catherine Lucy Wilhelmina Powlett, Duchess of Cleveland (née Stanhope), was born on 1 June 1819 in Mayfair, London. She was the third child and only daughter of Philip Henry Stanhope, 4th Earl Stanhope (1781–1855), a Fellow of the Royal Society, and his wife, Hon. Catherine Lucy Smith, daughter of Robert Smith, 1st Baron Carrington. She was known as Wilhelmina to differentiate her from her mother.

At the accession of Queen Victoria in 1837, Wilhelmina Stanhope was 18 years old and was regarded as one of the most beautiful women at the royal court. She served as a train-bearer at Queen Victoria's coronation in 1838 and was a bridesmaid at the queen's wedding to Prince Albert in 1840.

In October 1843, Wilhelmina married Archibald Primrose, Lord Dalmeny, who was born in 1809 and was the eldest son of Archibald Primrose, 4th Earl of Rosebery (1783–1868). The couple met three months prior at Buckingham Palace. They had four children: two sons and two daughters. Their children included Archibald Philip Primrose (1847–1929), who succeeded as the 5th Earl of Rosebery and served as Prime Minister of the United Kingdom; Lady Constance Evelyn Primrose (died 1939), who married Henry Wyndham, 2nd Baron Leconfield; Lady Mary Catherine Constance Primrose (circa 1845–1935), who married Henry Walter Hope; and Everard Henry Primrose (1848–1885), who died unmarried. Lord Dalmeny's death in 1851 was attributed to heart failure.

In 1854, Wilhelmina remarried to Lord Harry Vane (1803–1891), the youngest son of William Vane, 1st Duke of Cleveland. In 1864, Lord Harry Vane succeeded his brother as Duke of Cleveland and changed his surname to Powlett. The marriage produced no children. Following the death of the 1st Duke of Cleveland in 1864, his titles generally became extinct, with the exception of the barony of Barnard.

Catherine Lucy Wilhelmina Powlett was also known for her scholarly pursuits. She authored several historical works, notably "The Battle Abbey Roll with some Account of the Norman Lineages," published in three volumes in 1889, which details the origins of numerous English families of Norman descent based on legendary names associated with the Battle Abbey Roll. Her other publications include "The True Story of Kaspar Hauser from Official Documents" in 1893, concerning her father's patronage of the mysterious youth Kaspar Hauser, and "The Life and Letters of Lady Hester Stanhope" in 1914, about her father's half-sister, Lady Hester Stanhope, a traveler and Arabist.

Catherine Lucy Wilhelmina Powlett died unexpectedly of a cardiac arrest on 18 May 1901 in Wiesbaden, Hesse, shortly before her 88th birthday. Her death followed a successful eye surgery. Her obituary in The Times remarked on her endurance as a traveler and her sustained faculties and interests into old age.