Oliver Stanley Oliver Frederick George Stanley MC , PC ( 4 May 1896 – 10 December 1950 ) was a prominent British Conservative politician who held many ministerial posts before his early death when it was expected he would soon assume higher office . Background and education . Stanley was the second son of Edward Stanley , 17th Earl of Derby , by his wife Lady Alice , daughter of William Montagu , 7th Duke of Manchester . Edward Stanley , Lord Stanley was his elder brother . He was educated at Eton . Military career . The Hon . Oliver Stanley was commissioned into the Lancashire Hussars in the First World War , serving for part of it attached to the Royal Artillery , reaching the rank of captain , and winning the Military Cross . Political career . Stanley then entered the legal profession , but in the 1924 general election he was elected as Member of Parliament ( MP ) for Westmorland . From 1945 he sat for Bristol West . He soon came to the attention of the Conservative leaders and held a number of posts in the National Government of the 1930s . As Minister of Transport he was responsible for the introduction of a 30 miles per hour speed limit and driving tests for new drivers . In May 1938 whilst President of the Board of Trade he achieved a rare distinction in British politics when his brother Lord Stanley became Secretary of State for Dominion Affairs - a rare example of two brothers sitting in the same Cabinet , more so as their father , a former Conservative minister , was still alive . However five months later Edward died . ( Another example is David Miliband and his brother Ed Miliband who were appointed to the British Cabinet in June 2007 . ) In January 1940 Stanley was appointed Secretary of State for War after the previous incumbent , Leslie Hore - Belisha , had been sacked after falling out with the leading officers . Much was expected of Stanley ' s tenure in this office , as his father had held it during the First World War , but four months later the government fell and Stanley was not initially given a new post in the administration of Winston Churchill . Two years later Stanley ' s fortunes revived when Churchill appointed him Secretary of State for the Colonies , a post which he held until the end of the war . After the Conservatives ' massive defeat in the 1945 general election Stanley was prominent amongst those rebuilding the party and he came to be regarded as one of the most important Conservative MPs . Also during this period he succeeded his father as Chancellor of the University of Liverpool . By this time , however , his health was in decline and he died in December 1950 . Many believe that had he lived longer he would have been appointed Chancellor of the Exchequer when the Conservatives formed a government the following year . Family . Stanley married Lady Maureen , daughter of Charles Vane - Tempest - Stewart , 7th Marquess of Londonderry and the Hon . Edith Chaplin , in 1920 . They had one son and one daughter : ( i ) Michael Charles Stanley ( 1921 – 1990 ) , who married ( Aileen ) Fortune Constance Hugh Smith and had two sons ; and ( ii ) Kathryn Edith Helen Stanley DCVO ( 1923 – 2004 ) , Lady - in - Waiting to Queen Elizabeth II from 1955 to 2002 and who married Sir John Dugdale KCVO ( 1923 – 1994 ) and had two daughters and two sons , one of whom , Henry Dugdale ( b . 1963 ) is married to Litia Mara Dugdale . Lady Maureen died in June 1942 , aged 41 . Stanley survived her by eight years and died in December 1950 , aged 54 .