Michael Stewart was born in Bromley [London] on 6 November 1906, the son of Robert Wallace Stewart, author and lecturer and Eva Stewart, (née Blaxley). He was educated at Brownhill Road Elementary School, Catford, then Christ's Hospital, Horsham [West Sussex] and finally St. John's College, Oxford, graduating with a first class BA in philosophy in 1929. On 26 July 1941 he married Mary Elizabeth Henderson Birkinshaw; they had no children.

While still at university, Stewart was President of the Oxford Union, and of St John's Labour Club (1929). Following graduation, he worked temporarily with the Secretariat of the League of Nations, before becoming an Assistant Economics Master, first at Merchant Taylors’ School in London, (1930-31), then Coopers’ Company’s School, Mile End, then from 1939 at Frome [Somerset]. He also taught as a part-time tutor in economics and international affairs for the University of London Tutorial Classes Committee and Workers' Educational Association, (1931-42). During the war, Stewart served in the Middle East, joining the Intelligence Corps in 1942, then transferring to the Army Educational Corps, 1943; he was commissioned and promoted to Captain in 1944.

Stewart had contested West Lewisham in 1931 and 1935, and East Fulham in 1936; after the war he became Labour MP for Fulham East, (1945-55), then for Fulham, (1955-74), and Hammersmith, Fulham, (1974-79). His political appointments included: Junior Lord of the Treasury and Vice-Chamberlain of the Royal Household, (1946-47); Comptroller of the Royal Household, (1946-47); Leader of Parliamentary delegation to South America (1947); Under-Secretary of State for War, (1947-51); Parliamentary Secretary, Ministry of Supply, (May-October 1951); Shadow Minister of Education, (1955-59); Shadow Minister of Housing and Local Government, (1959-64); Secretary of State for Education and Science, (October 1964-January 1965); Foreign Secretary, (January 1965-August 1966); First Secretary of State, (1966-68); Chancellor of the Exchequer, (August 1966-67); Secretary of State for Foreign and Commonwealth Affairs, (1968-70); Commissioner, Procurator, and Plenipotentiary of Great Britain and Northern Ireland, (October 1968); member of the European Parliament, (1975-76); introduced to the House of Lords as a life peer, (July 1979).

Stewart's honours and other positions include: Privy Councillor (1964); Honorary Fellow, St John’s College, Oxford, (1965); Honorary Doctor of Laws, University of Leeds, (1966); Companion of Honour (1969); Leader of the Labour Delegation to the Council of Europe (June 1970); joint president of the Labour Committee for Europe with George Brown and Roy Jenkins (October 1970); Honorary Doctor of Science, Benin, (1972); Member of the Subcommittee on Reform of the House of Lords, (1980); Founder member and Vice-President of the Economics Association (1981).

Stewart's publications include: The Forty Hour Week (Fabian Society), (1936); Bias and Education for Democracy, (1937); The British Approach to Politics, (1938); Modern Forms of Government, (1959); his autobiography Life and Labour, (1980); European Security: the case against unilateral nuclear disarmament, (1981); many articles and contributions to journals. He died on 10 March 1990.

Mary Stewart was born in Bradford [Yorkshire] on 8 May 1903, the daughter of the commercial traveller Herbert Birkinshaw and Isabella Henderson Birkinshaw. She was educated at King Edward VI High School, Birmingham [Warwickshire], and Bedford College, University of London, graduating with a BA in philosophy in 1928. She married Robert Godfrey Goodyear on 24 December 1931, but they were divorced on 26 May 1941, and she then married Stewart on 26 July 1941.

During the war, Mary Stewart served as Senior Marshall for the St Pancras air raid shelter, (June 1940-February 1941), and worked on the wards in Brentford [Essex] (September-December 1941). She then joined the Women's Auxiliary Air Force, (December 1941-45), serving at W.A.A.F. depots in Gloucester (December 1941-January 1942), Morecambe [Lancashire] (January-February 1942) and Bridgnorth [Shropshire] (February-April 1942). She was commissioned as Assistant Section Officer in June 1942, then served in the W.R.A.F. at Great Bromley, [Essex] (June-October 1942), Barkway [Hertfordshire] (November 1942-February 1943), Swanage [Dorset] (March-July 1943), as a Psychiatric Assistant at W.R.A.F. Newtownards [County Down, Northern Ireland] (August 1943-January 1944), in the London Headquarters, (January-March 1944) and Eastchurch [Kent] (March 1944-April 1945).

Stewart had worked for the Workers Educational Association, as a lecturer (1940-December 1941), and after the war returned to the WEA as a tutor until 1964. She became a member of the Fabian Society Executive, (1950-85), serving as Chairman in 1963-64, and was also Chairman of the Governors of Charing Cross Hospital [London], (1966-74), of the East London Juvenile Court, (1956-66) and of Fulham-Gilliatt Comprehensive School, (1974-79), while also a member of the Joint Governing Body, Fulham Gilliatt and Mary Boon Schools, (1980)– She was a Justice of the Peace for London, (1949) and also held the position of Honorary President of the Diplomatic Service Wives' Association until 1970. She was created a life peer as Baroness Stewart of Alvechurch in December 1974.

Her publications include many articles, and Fabian Society pamphlets. Baroness Stewart died on 28 December 1984.