He was elected to the House of Commons as Member of Parliament (MP) for Newark in 1922, a seat he held until he succeeded his father in the dukedom in 1943, and served as a Junior Lord of the Treasury under Stanley Baldwin from 1927 to 1929 and under Ramsay MacDonald in 1932.

They had two daughters:[2] He died in March 1977, aged 84, and was interred at the traditional burial place of the Dukes of Portland, in the churchyard of St Winifred's Church at Holbeck.

Lady Margaret had been married to Don Gaetano Parente, Principe di Castel Viscardo, Italy.

Her son, named William Henry Marcello Parente (born 18 February 1951), inherited the estates and later served as High Sheriff of Nottinghamshire in 2003.

His probate was sworn in 1977 at £4,391,478 (equivalent to about £34,500,000 in 2023), three times that of his father's assets passing at point of death (in real terms).