Bottomley was born in Newport, Shropshire, the son of Sir James Bottomley, a wartime British Army officer who later made his career in the Foreign and Commonwealth Office, and of Barbara, née Vardon, a social worker. He was baptized at St Swithun's parish church at Cheswardine where his parents had married. After seven school changes before the age of eleven, he was educated at a junior high school in Washington, D.C. and then Westminster School before reading economics at Trinity College, Cambridge, following his father, grandfather, father-in-law and father-in-law's father to the College. His supervisor was James Mirrlees, who later gained the Nobel prize for Economics. Before university he worked around Australia including three weeks teaching at Geelong Grammar School and unloading trucks in Melbourne docks. In between, he spent a week in Mt. Field with Tenzing Norgay and Jenny Smithies of Launceston Methodist Ladies College. After university, he became a lorry driver and joined the Transport and General Workers Union before moving on to industrial sales and industrial relations. In the early 1970s he co-founded the Neighbourhood Council in South Lambeth, resulting in the creation of football pitches and other facilities at Larkhall Park. His last job before entering Parliament was putting lights outside theatres and cinemas in London's West End.
Bottomley contested the Woolwich West parliamentary seat in the February and October general elections of 1974, failing to defeat the sitting Labour MP William Hamling. Hamling died on 20 March 1975, and in the space of 18 months, Bottomley faced the electors of Woolwich West for a third time at the by-election on 26 June 1975. He was then elected as the Conservative MP for Woolwich West with a majority of 2,382, and he held this marginal seat and its successor, Eltham, in Parliament for the next 22 years.
In 1978 he became the President of the Conservative Trade Unionists, a position he held for two years. Before the 1979 general election, Bottomley became a trustee with Christian Aid in 1978 until 1984. In 1978 as a member of the Parliamentary Human Rights Group, he campaigned to help delay the anticipated assassination of Archbishop Oscar Romero and represented the British Council of Churches at the funeral in El Salvador in 1980 when 14 people died around him. In 1979, days before the fall of the Labour Government, he made a visit to Washington DC to indicate that Margaret Thatcher, if she became Prime Minister, would not lift sanctions on Southern Rhodesia nor recognise the government of Bishop Abel Muzorewa. He was for some years a member of the Conservative Monday Club despite disagreeing with their policies on immigration, race relations, Rhodesia and South Africa. He has been chairman of the Church of England's Children's Society, a trustee of Mind and of Nacro and on the policy committee of One Parent Families. He served on the successor committee to the Archbishop of Canterbury's commission Faith in the City and chaired the churches' review group on the Churches Main Committee. He is a member of the Ecclesiastical Committee and has been appointed the Parliamentary Warden at St. Margaret's Church, Westminster. He has led the United Kingdom delegation to the Parliamentary Assembly of the Organisation for Security and Co-operation in Europe (OSCE). He is vice chair of WATCH, Women and the Church, supporting full equal acceptance of females.
In 1982, he became the Parliamentary Private Secretary (PPS) to the Minister of State at the Foreign and Commonwealth Office, Cranley Onslow. Peter Bottomley's seat of Woolwich West had minor boundary changes and a name change during 1982. Bottomley fought the new constituency of Eltham at the 1983 general election, winning the seat with a majority of more than 7,500 votes. Following the election, Peter Bottomley became the PPS to the Secretary of State at the Department of Health and Social Security, Norman Fowler.
After nine years on the backbenches, Bottomley became a member of Margaret Thatcher's government when he was appointed as the Parliamentary Under Secretary of State at the Department for Employment in 1984, moving sideways to the Department of Transport in 1986 to become the Minister of Roads and Traffic. In 1989 he moved sideways again to the Northern Ireland Office. He was dropped by Thatcher in 1990, when he briefly became PPS to the Secretary of State for Northern Ireland, Peter Brooke. He has been a captain of the Parliamentary football team, participated in the parliamentary swimming competition and organised the annual dinghy sailing against the House of Lords. He was captain of the Commons eight, winning the first Thames rowing race in gigs against the Lords in 2007.
Since 1990 he has been a backbencher, described as a maverick, 'supporting a range of seemingly perverse causes'. Bottomley decided not to re-contest Eltham after major boundary changes, but sought nomination elsewhere. Following the retirement of the Conservative MP for Worthing Terence Higgins, Bottomley contested the newly formed constituency of Worthing West at the 1997 general election, gaining the seat with a majority of 7,700.
Bottomley is in more Parliamentary groups than any other MP. He was Chairman of the All-Party United Nations Group, is co-Chairman of PACTS the Parliamentary Advisory Council on Transport Safety and vice-chairman of the All Party Parliamentary Flag Group Through the Human Rights and CAFOD Groups he became and remained involved with the life, work and legacy of Oscar Romero since 1978. Through the Mental Health Groups he helped Charles Walker MP gain the first major debate on conditions lumped together as mental illness.
Bottomley has been a supporter of British pensioners living overseas, mainly in Commonwealth countries (47 out of 54) who have had their British state pensions frozen at the rates at which they were first paid or as at the dates of migration. British pensioners living in the remaining seven Commonwealth countries and those living in a number of non-Commonwealth countries have their British state pensions uprated each year, just as if they were living in the UK.
Bottomley was opposed to Brexit prior to the 2016 referendum.
Bottomley is Co-Chair to the APPG on Haemophilia and Contaminated Blood and campaigns to get justice for those affected by the Tainted Blood Scandal. During a debate in Parliament on 24 November 2016 he urged Prime Minister Theresa May to look at the issue. Many Campaigners and Politicians allege the scandal has been part of a Cover-Up.
In 1967 he married Virginia Garnett who later became a social scientist, an MP, a Cabinet Minister, and a life peer as Baroness Bottomley of Nettlestone. They have a son and two daughters. The couple have homes in Worthing, West Sussex, Milford, Surrey and Westminster.
His brother was a Lambeth councillor; his brother-in-law was Mayor of Cambridge. His niece is Kitty Ussher, the economist, former Labour MP and Minister. His great-grandfather Sir Richard Robinson led the Municipal Reformers to victory in the 1907 London County Council election. In 2002-2003 he was Master of the Worshipful Company of Drapers.
In 2003 he was banned from driving for 6 months following several speeding offences.
Bottomley was knighted in the 2011 New Year Honours for public service.
In 1989 he successfully sued The Mail on Sunday, the Daily Express and News of the World for allegations connected with his support of the union membership of a social worker in his constituency accused of misbehaviour in a children's home. In 1995 he was awarded £40,000 against the Sunday Express for an article that depicted him as having behaved in treacherously disloyal and disreputable manner.