Matthew Alan Oakeshott was born 10 January 1947 to Keith Robertson Oakeshott, CMG, and Eva (née Clutterbuck). Oakeshott was educated at Charterhouse School before attending University College, Oxford and Nuffield College, Oxford, graduating with a MA.
Oakeshott worked in the Ministry of Finance and Economic Planning of Kenya from 1968 to 1970. During 1970 to 1972, he undertook post-graduate studies at Nuffield College, Oxford, although he did not complete a graduate degree. He joined the Labour Party and served as a Councillor on Oxford City Council.
He stood twice, unsuccessfully, for election to the House of Commons of the United Kingdom. As a Labour parliamentary candidate he fought the Horsham and Crawley seat in 1974, and then as the SDP–Liberal Alliance candidate for the seat of Cambridge in 1983.
From 1972 to 1976, Oakeshott was a Parliamentary Assistant to Labour's Roy Jenkins in Opposition: a so-called "Chocolate Soldier" funded by the Joseph Rowntree Social Service Trust. When Jenkins became Home Secretary, Oakeshott worked as his Special Advisor. Jenkins charged him with keeping 'an eye on the Common Market 'negotiation' by forging a close relationship with George Thomson's cabinet in Brussels, but also to keep him in touch with Labour party feeling and help write speeches and newspaper articles.' He was an instrumental part of the team that wrote the Limehouse Declaration Owen described him as ' an EEC 'federalist'.
After this, Oakeshott became a Director of Warburg Investment Management, a post which he held until 1981, and then investment manager of the Courtaulds pension fund until 1985. He was a founder director of OLIM in 1986 and is now Chairman of OLIM Property Limited, which invests in commercial property throughout the UK for pension funds, investment trusts and charities. He is joint investment director of Value and Income Trust plc (VIN).
He was created a Life Peer as Baron Oakeshott of Seagrove Bay, of Seagrove Bay in the county of Isle of Wight on 1 May 2000, serving as Liberal Democrat Treasury Spokesman in the House of Lords from 2001 to 2011 and as Pensions Spokesman from 2002 to 2010. He has been a leading enthusiast for reform of the House of Lords.
From the formation of the Coalition Government in May 2010 until his resignation from the Lib Dems in May 2014, Lord Oakeshott was highly critical of the Coalition's policies. He stood down as HM Government Treasury Spokesman by "mutual agreement" in February 2011, after his description of the Coalition's Project Merlin deal with the banks over lending and bonuses as being "pitiful". He was then critical of its economic policy, where he has particularly opposed the cut in the top rate of tax to 45p and the "austerity measures". He opposed key Coalition legislation such as the Health and Social Care Act and elected Police Commissioners. He called for Conservative Cabinet Minister Jeremy Hunt to resign over his handling of BSkyB, and in July 2012 referred to Conservative Chancellor of the Exchequer George Osborne as a "work-experience Chancellor" suggesting that he should resign and be replaced by Vince Cable. He supported Francois Hollande to become President of France, despite many in the Coalition backing Sarkozy.
In 2012 he was already concerned about the future of the Lib Dems being highly critical of Nick Clegg's leadership. During the latter part of 2013, Oakeshott began to call for Nick Clegg to resign as Leader of the Liberal Democrats, even suggesting that the Coalition may have to break apart. In April 2014 he privately commissioned ICM Research to undertake a telephone poll in each of four key Lib Dem seats: Clegg's own Sheffield Hallam; Cambridge; Redcar; and Wells. The results indicated that the Lib Dems would pick up votes if another figure replaced Clegg as party leader, and also suggested that the party was on course to lose the four seats in the 2015 UK general election unless there was a change of Lib Dem leader. After the poll results were leaked via The Guardian newspaper on 27 May 2014, and Clegg on 28 May accused him of seeking to "undermine" the Lib Dems and warned he faced disciplinary action, Oakeshott subsequently resigned from the party and took a "leave of absence" from the House of Lords.
In an attempt to "help save our country from a Tory government cringing to Ukip" in January 2015 he donated £300,000 in total to 15 Labour candidates in the 2015 General Election, £300,000 to 15 Liberal Democrats and £10,000 to the Green Party's sole MP, Caroline Lucas. In February 2015, Oakeshott was pictured wearing a red rossette and canvassing for Labour in Thurrock.
In 1976, he married Philippa Poulton, a medical doctor. They have two sons, Joseph and Luke, and one daughter, Rachel. He is related to journalist Isabel Oakeshott.Chapter in By-Elections in British Politics (1973)