Cavendish needs to be distinguished from his first cousin and namesake, Sir William Cavendish I*, subsequently 2nd earl of Devonshire. His father, Sir Charles Cavendish, sat for Nottinghamshire in 1593 and 1601 and was the youngest son of Sir William Cavendish†, treasurer of the chamber under three Tudor monarchs, and ‘Bess of Hardwick’.
In her biography of him, Cavendish’s second wife states that he ‘never showed a great inclination’ to scholarship and that his tutors at Cambridge ‘could not persuade him to read or study much, he taking more delight in sports, than in learning’. Nevertheless his aunt, the countess of Shrewsbury, was a benefactress of St. John’s, which presumably explains how Cavendish came to be awarded an MA in 1608. Although no scholar, Cavendish was devoted to music, and under his father’s guidance he also developed into one of the finest horsemen in the kingdom.
Two years later, still under age, Cavendish was elected for East Retford, at the nomination of his uncle, the 7th earl of Shrewsbury, the high steward of the borough.
Cavendish was described by the duchess of Newcastle as of a ‘sweet, gentle, and obliging nature’, who ‘to the meanest person he’ll put off his hat, and suffer everybody to speak to him’. She also wrote that he was ‘a great lover and admirer of the female sex’. He failed in his first courtship because the lady’s step-father, Sir Edward Coke*, insisted on marrying her to Buckingham’s brother. Shortly afterwards, however, he secured a much wealthier bride who brought him £2,400 a year in land, and over £6,000 in money.
Cavendish was elevated to the peerage before the elections for the 1621 Parliament. Although no money seems to have changed hands he effectively purchased the title in return for surrendering his claims to part of the estate of the earl of Shrewsbury, who had died in 1616. Shrewsbury had appointed Cavendish one of his executors but the latter sued Shrewsbury’s three daughters and coheirs, the countesses of Pembroke and Arundel and Lady Grey, claiming a right to a significant portion of the lands. The peerage was granted at the request of the earl of Arundel and Cavendish promptly abandoned his suit.
In July 1626 the Nottinghamshire lieutenancy was revived for Mansfield, probably as reward for his support for the duke of Buckingham, and he was also appointed to the bench.
