His mother, Frances Anne Crewe, the daughter of Fulke Greville, was a political hostess known for her great beauty and wit.

[1][2] His younger sister, Elizabeth Emma (1780–1850), married Foster Cunliffe-Offley; two other siblings, Richard and Frances, did not survive infancy.

[2] As a child in around 1775, he was painted by Sir Joshua Reynolds in a pose and costume that mimic the well-known portrait of Henry VIII by Hans Holbein the Younger.

[3] The portrait is considered among the artist's finest portrayals of children,[4] and has been described as "one of Reynolds' freshest attempts at comedy painting".

[5] Horace Walpole commented: "Is not there humour and satire in Sir Joshua's reducing Holbein's swaggering and colossal haughtiness of Henry VIII to the boyish jollity of Master Crewe?

[7] Local historian Ray Gladden describes him at the time of his entrance into the army as "high spirited", accruing gambling debts that his father had to pay off by selling land.

"[13] Following the abolition of slavery in 1833, Crewe was one of those awarded compensation by Parliament for the loss of his "property" at Four Hills and The Rock, sugar plantation estates on Barbados that he had acquired through his wife.

[9][18] His older daughter, Henrietta, moved to Belgium to live with her father, and subsequently converted to Roman Catholicism.

She returned to England after her father's death and never married, maintaining an establishment for many years in the grounds of Prior Park, Bath.

[8] Lord Crewe died at Bois l'Evèque in 1835, and is buried at Barthomley, Cheshire, where the family chapel is located.