Hain was born in Nairobi in what was then Kenya Colony, but he moved to the Union of South Africa about a year later. His parents, Walter Vannet Hain and Adelaine Hain née Stocks, were anti-apartheid activists in the Liberal Party of South Africa, for which they were made "banned persons", briefly imprisoned, and prevented from working. Hain's paternal grandparents, civil engineer Walter Vannet Hain of Dundee, and Mary Hain née Gavin of Glasgow, married in 1919, leaving Shettleston, Lanarkshire, on 17 September 1920 on the Edinburgh Castle with their new-born baby William Ayers Vannet Hain, sailing from Southampton to South Africa. Hain's father, later to become an architect, was born there on 29 December 1924. Hain's maternal grandparents were of notable 1820 Settler British South African stock. His 4th great-grandfather was George Southey (1776–1831) who hailed from Devonshire. Hain descends from his daughter, Sophia Stirk née Southey, whose brother George was famous for helping to track the Xhosa tribal chief Hintsa kaKhawuta (ca. 1790 – 1835), pursuing him through the defiles of the Fish River bush, when Colonel, afterwards Sir Harry Smith was engaged in his capture, and who, at a critical moment, when the chief had already thrown his assegai at Colonel Smith, and would certainly have killed him, shot him dead through the back of his head, despite his pleas for mercy. Southey then mutilated the body. A brother of Sophia and George Southey was Sir Richard Southey a British colonial administrator, cabinet minister and landowner in South Africa. Hain is a fifth cousin six times removed of the Poet Laureate Robert Southey.
When Hain was 10, he was awoken in the early hours by police officers searching his bedroom for 'incriminating documents'. At 15, Hain spoke at the funeral of John Frederick Harris, an anti-apartheid activist who was hanged for murder for the bombing of the Johannesburg main railway station, injuring 23 people and killing an elderly woman, Mrs Ethyl Rhys. Mrs Rhys's grand daughter suffered severe burns. As a result of security police harassment, Hain's father was unable to continue his work as an architect, and the family decided to leave for the United Kingdom in 1966.
Hain was educated at Pretoria Boys High School and at Emanuel School, the latter of which eventually becoming a private fee-paying institution, then Queen Mary College (University of London), graduating with a first class Bachelor's degree in Economics and Political Science in 1973, and the University of Sussex, obtaining an MPhil. After university, Hain worked as a researcher for the Union of Communication Workers, rising to become their head of research.
Hain became chairman of the Stop The Seventy Tour campaign which disrupted tours by the South African rugby union and cricket teams in 1969 and 1970. In 1971 director John Goldschmidt produced a film for Granada's World in Action programme featuring Peter Hain debating Apartheid in South Africa at the Oxford Union. The film was transmitted on the ITV network. In 1972 Hain was convicted of criminal conspiracy in a trial at the Old Bailey and fined £200.
In 1972 he was sent a letter bomb that failed to explode because of faulty wiring. In 1976 Hain was tried for, and acquitted of, a 1974 bank robbery, allegedly having been framed by the South African Bureau of State Security (BOSS).
He joined the Liberal Party and was elected chairperson and then president of the Young Liberals, but in 1977 switched to Labour. The same year, he was a founder of the Anti-Nazi League and he remains a prominent supporter of Unite Against Fascism today.
He contested Putney in the 1983 and 1987 general elections but was defeated on both occasions by Conservative David Mellor.
He was elected to the House of Commons at the by-election in April 1991 for the Neath constituency that followed the death of the sitting member, Donald Coleman. In 1995 he became a Labour whip and in 1996 became a shadow employment minister.
After Labour's victory in the 1997 general election he joined the government, first at the Welsh Office 1997–1999, then as minister of state at the Foreign and Commonwealth Office from 1999–2001.
In November 1999, as Africa minister he entertained Robert Mugabe in London who told him "I know you are not one of them, Peter; you are one of us," But the following day, following an attempt by Gay Rights campaigner Peter Tatchell to carry out a 'citizen's arrest' on Mugabe, Mugabe accused Hain of being Tatchell's "wife". In October 2000 he set up a war avoidance team to carry messages back and forth between himself and the then-Minister of Foreign Affairs in Iraq, Tariq Aziz (a matter then confidential, which has since been put on public record in an interview with Hain by the Today programme). Team members who travelled repeatedly to Iraq on behalf of Hain variously included William Morris, Burhan Chalabi (an Iraqi-born British businessman), and Nasser al-Khalifa (the then-Qatari Ambassador to the UK). He voted for the invasion of Iraq in 2003, later calling it a "fringe issue".
In 2001 Hain moved briefly to the Department of Trade and Industry before returning to the Foreign Office as Minister for Europe, being sworn of the Privy Council the same year. He was vocal in advocating joint sovereignty of Gibraltar with Spain and was accused of deliberately misrepresenting the situation. The agreement was described by Michael Ancram in the UK Parliament, along with Gibraltar as a 'sell-out' which was overwhelmingly rejected in a referendum in November 2002. He remains one of the most unpopular politicians ever to visit Gibraltar.
In October 2002, he joined the Cabinet as Secretary of State for Wales, but continued to represent the UK at the Convention on the Future of Europe. In June 2003 he was made Leader of the House of Commons and Lord Privy Seal in a cabinet reshuffle, but retained the Wales portfolio. In November 2004 Hain caused controversy among his political rivals when he claimed that "If we are tough on crime and on terrorism, as Labour is, then I think Britain will be safer under Labour".
On 6 May 2005, following the 2005 general election, Hain was appointed as Secretary of State for Northern Ireland, retaining his Welsh position also. Although previously a supporter of Irish unity, he has since retreated from this position. On 28 June 2007, he was appointed as Secretary of State for Work and Pensions in addition to retaining responsibility for Wales. He was a proponent of the "tough love" measures designed to force claimants, including the sick and disabled, back to work. He saw it as an anti-poverty, full-employment agenda. He resigned from his post when the issue of donations made to his campaign funds were referred to the police.
He set a level of compensation for the taxpayer funded Financial Assistance Scheme similar to that of the Industry funded Pension Protection Fund (PPF) for those whose schemes had collapses before the establishment of the PPF. Referring to the long running Pensions Action Group campaign and speaking on the BBC Radio 4 Moneybox program on the day compensation was announced, pensions expert Ros Altmann, credited Hain and Mike O'Brien with "having been very different to deal with than their predecessors and..willing and eager to engage and find a way to sort this out."
On 12 September 2006, he announced his candidacy for the position of Deputy Leader of the Labour Party. In January 2007, Hain gave an interview to the New Statesman in which he made his pitch for the Deputy Leadership and referred to the Bush administration as "the most right-wing American administration, if not ever, then in living memory" and argued that "the neo-con agenda for America has been rejected by the people and I hope that will be the case for the future". Hain was eliminated in the second round of the Deputy Leadership election, coming fifth out of the six candidates, with Harriet Harman being the successful candidate.
In January 2008, The Guardian reported that Hain had failed to declare some 20 donations worth a total of over £100,000 during his deputy leadership campaign and would be investigated by the Electoral Commission. Hain admitted "deeply regrettable administrative failings" but faced questioning on whether the oversight was due to changes in campaign manager possibly causing "chaos" during the campaign or the desire of some donors to remain private. Phil Taylor, the first campaign manager, said that Hain insisted on knowing who had donated and that it was legal. His campaign only reported a separate £82,000 of donations and the Guardian believes he stopped taking a personal interest in funding once the campaign ended though there was no evidence that he deliberately broke the law. Isaac Kaye, who had previously paid the National Party in South Africa, also made a payment to the campaign for Labour Deputy Leadership.
Taylor's successor was Steve Morgan, and it later emerged that four donations were channelled through a non-operating think tank, the Progressive Policies Forum (PPF) which may be connected with Morgan, who was named as a donor. On 12 January, Peter Hain released a statement saying that he wanted to get on with his job and it was absurd to think he had deliberately hidden anything. John Underwood, a trustee of the PPF, said that the donations and loans were "entirely permissible", though Hain said he would pay back a £25,000 interest-free loan.
On 24 January 2008, he resigned from several posts including his position as Work and Pensions secretary, after the Electoral Commission referred the failure to report donations to Metropolitan Police. He cited a desire to "clear his name" as the reason for his resignation. Peter Hain was the first person to resign from Gordon Brown's cabinet. He was replaced as Secretary of State for Wales by Paul Murphy, and as Secretary for Work and Pensions by James Purnell in a forced cabinet reshuffle.
Hain's campaign failed to declare £103,156 of donations, contrary to electoral law. On 3 July 2008, the Metropolitan Police announced that they had referred Peter Hain's case to the Crown Prosecution Service. On 5 December 2008 the CPS announced that Hain would not be charged because Hain did not control the members' association Hain4Labour that funded his campaign.
He was a supporter of the unsuccessful Alternative Vote system in the May 2011 referendum, together with his close friend and fellow ex-Young Liberal Richard Burden MP.
On 27 March 2012, the Attorney General for Northern Ireland, John Larkin QC obtained leave from Lord Justice Higgins to bring proceedings against Hain and "Biteback Publishing" for contempt of court. Although Hain's book Outside In had already been passed by the Cabinet Office and the Northern Ireland Office prior to publication, the alleged contempt related to statements about Lord Justice Girvan's disposal of an application for judicial review while Hain was Secretary of State.
Hain's remarks had previously been strongly criticised by the Lord Chief Justice of Northern Ireland, Sir Declan Morgan though the decision to charge Hain with "scandalising the court", using a law already obsolete in 1899 drew ridicule in Westminster and strong criticism from senior DUP ministers. According to the Attorney General, Hain's statements prejudiced the administration of justice and amounted to an unjustifiable attack on the judiciary. At a preliminary hearing before a Divisional Court of the Queen's Bench Division of the High Court of Justice on 24 April 2012, Hain's counsel suggested that the action had no basis in common law and was contrary to the European Convention on Human Rights. The trial was intended to take place on 19 June 2012 but the case was dropped on 17 May 2012 after Hain agreed to clarify comments to show he didn't question Girvan's motives or his handling of the judicial review.
Hain was created a life peer taking the title Baron Hain, of Neath in the County of West Glamorgan on 22 October 2015.1950–1991: Mr Peter Hain
1991–2001: Mr Peter Hain
2001–2015: The Rt Hon. Peter Hain
2015: The Rt Hon. Peter Hain
2015–: The Rt Hon. The Lord Hain
Hain has written in support of libertarian socialist arguments, identifying an axis involving a "bottom-up vision of socialism, with anarchists at the revolutionary end and democratic socialists [such as himself] at its reformist end", as opposed to the axis of state socialism with Marxist-Leninists at the revolutionary end and social democrats at the reformist end. Hain has argued for "encouraging industrial democracy. This is one of the keys to the high productivity, investment and wealth needed for economic success, by helping generate greater team working and commitment which is such an important requirement of complex modern production systems."
The renewed campaign for construction of the Severn Barrage by Hafren Power was led by Hain in 2012, until Hafren Power wound up in 2014.
On 28 October 2015, Hain was appointed to the Board of AIM listed vertically integrated fertiliser company, African Potash, as Non-Executive Director.
He is a member of the Advisory Council for the College of Medicine, an alternative medicine lobbying organisation set up following the disbanding of Charles, Prince of Wales's Foundation for Integrated Health in the wake of a fraud investigation. Describing its mission as "to take forward the vision of HRH the Prince of Wales" and originally called "The College of Integrated Health," several commentators, writing in The Guardian, The British Medical Journal and in the blogosphere, claim that this organisation is simply a re-branding of the controversial Foundation. It continues to act as an alternative medicine lobby group. The College has been referred to as "Hamlet without the Prince."
Hain lives in Resolven in the Neath Valley. He married his first wife Patricia Western in 1975, and they have two sons. In June 2003, he married his second wife, executive recruitment consultant Elizabeth Haywood, in Neath Register Office.Peter Hain (1971). Don't Play with Apartheid: Background to the Stop the Seventy Tour Campaign. Allen & Unwin. ISBN 978-0043010310.
Radical Liberalism and Youth Politics by Peter Hain, 1973, Liberal Publications Department ISBN 0-900520-36-1
Radical Regeneration by Peter Hain, 1975, Quartet Books ISBN 0-7043-1231-X
Peter Hain, ed. (1976). Community Politics. Calder Publications Ltd. ISBN 0-7145-3543-5.
Mistaken Identity: The Wrong Face of the Law by Peter Hain, 1976, Quartet Books ISBN 0-7043-3116-0
Peter Hain and Simon Hebditch (1978). Radicals and Socialism. Institute for Workers' Control. ISBN 0-901740-55-1.
Policing the Police Edited by Peter Hain, 1979, J Calder ISBN 0-7145-3624-5
Peter Hain, ed. (1980). Debate of the Decade: The Crisis and Future of the Left. Pluto Press. ISBN 0-86104-313-8.
Neighbourhood Participation by Peter Hain, 1980, M. T. Smith ISBN 0-85117-198-2
Policing the Police Edited by Peter Hain, 1980, J Calder ISBN 0-7145-3796-9
Peter Hain (1980). Reviving the Labour Party. Institute for Workers' Control. ISBN 0-901740-69-1.
Peter Hain (1983). The Democratic Alternative: A Socialist Response to Britain's Crisis. Penguin Books Ltd. ISBN 0-14-006955-0.
Peter Hain (1985). Political Trials in Britain. Penguin Books Ltd. ISBN 0-14-007935-1.
Peter Hain (1986). Political Strikes: The State and Trade Unionism in Britain. Penguin Books Ltd. ISBN 0-14-007962-9.
Proportional Misrepresentation by Peter Hain, 1986, Gower Publishing Ltd ISBN 0-7045-0526-6
Peter Hain (1987). A Putney Plot?. Spokesman Books. ISBN 0-85124-481-5.
Peter Hain (1995). Ayes to the Left. Lawrence & Wishart Ltd. ISBN 0-85315-832-0.
Peter Hain (1995). The Peking Connection. Lawrence & Wishart Ltd. ISBN 0-85315-823-1.
Peter Hain (1996). Sing the Beloved Country: Struggle for the New South Africa. Pluto Press. ISBN 0-7453-0997-6.
Robin Cook and Peter Hain (2001). The End of Foreign Policy?. Royal Institute of International Affairs. ISBN 1-86203-131-2.
New Designs for Europe by Katinkya Barysch, Steven Everts, Heather Grabbe et al., introduction by Peter Hain, 2002, Centre for European Reform ISBN 1-901229-35-1
The Future Party by Peter Hain and Ian McCartney. Catalyst Press. 2004. ISBN 1-904508-10-3.
Outside in (autobiography), Biteback (23 January 2012), ISBN 978-1-84954-118-3
Back to the future of socialism, Policy Press (26 January 2015), ISBN 978-1-44732-166-8