Before the parliamentary reorganisation of 1945, Slough was part of the Wycombe Constituency. During this time, MPs included Lord Curzon, who went on to become Viceroy of India, and William Grenfell who later became Lord Desborough.

The new constituency of Eton and Slough was first contested in the 1945 General Election, and was won by the playwright Benn Levy, who had co-written Alfred Hitchcock's first talkie, 'Blackmail', in 1929. While in Parliament he introduced a Private Member's Bill to abolish stage censorship, but this was unsuccessful.

Levy stood down as an MP in 1950, and in subsequent years served on the Executive of the Arts Council, and as Chairman of the League of British Dramatists. In his later years he established a breed of Fresian cattle on his farm in Oxfordshire.

Levy was succeeded as MP for Eton and Slough by Fenner Brockway. Brockway had been converted to socialism by Keir Hardy in 1907. He was prosecuted 9 times as a conscientious objector in World War 1, and spent almost 3 years in jail. In 1948 he helped set up the Peoples Congress against Imperialism, and in 1954 founded the Movement for Colonial President, of which he was the President for many years.

Brockway was Sloughs' MP until 1964. Following his defeat in this election he was made a life peer, choosing the title Baron Brockway of Eton and Slough. He was actively opposed to the arms race. He was instrumental in setting up CND, and also co-founded the World Disarmament Campaign (UK) in 1979.

Brockway also served as Chairman of the Movement for Colonial Freedom, and Chairman of the British Asian and Overseas Socialist Fellowship. He died in 1988, just a few months short of his hundredth birthday.

In the 1964 election, Fenner Brockway was defeated by Anthony Meyer, by just 11 votes after 3 recounts. He was defeated by Joan Lestor in 1966, and describes his time as MP for Eton and Slough as "not particularly glorious". In later years he became known as a critic of the Thatcher government.

Joan Lestor became Slough's first woman MP at the age of 35. She also became the first MP to live in the constituency when she moved to Langley shortly after the election. She was given the nickname 'African Queen' because of her anti-apartheid views and her interest in the welfare of immigrants.

She was elected to the Labour Executive in 1967 and became Party Chairman in 1977. She was twice Under-Secretary for Education and Science, on one occasion resigning in protest at cuts in finance. She also served as Under-Secretary at the Foreign and Commonwealth Office.

In 1983, Joan Lestor was defeated by John Watts. He became Minister for Roads and Transport in 1994, and oversaw the privatisation of British Rail. In 1997, rather than continue as MP for Slough, he opted to contest a safer seat in Reading, but lost.

In 1997, Fiona McTaggart became Slough's latest MP. Her great-grandfather was Treasurer of the first ever Labour Party branch, set up by Keir Hardy. Before entering politics, she was National Secretary of the NUS, and ran the Joint Council for the Welfare of Immigrants.

McTaggart was inspired to enter politics by Fenner Brockway. On entering Parliament she became Parliamentary Aide to Culture Secretary Chris Smith, and in 2003 she became a minister in the Home Office - Parliamentary Under-Secretary for Race Equality, Community Policy and Civic Renewal. She has been Chairperson of the Parliamentary Labour Party Womens Committee since 2001.