Born in Lambeth to a Nigerian father and English-Irish mother, Umunna was educated at St Dunstan's College, a private school in Catford, Lewisham.

In 2021, Umunna joined JPMorgan Chase as Managing Director of its Environmental, Social, Governance (ESG) advisory group in London.

In 2006, he joined Rochman Landau (now Ashfords LLP), specialising in employment law and advising companies on contentious, transactional and advisory matters.

[14] From 2006, he began to write and provide commentary on the Labour Party, as well as broader social and economic issues, usually in his capacity as a member of the Management Committee of the Labour-aligned Compass pressure group.

[21][22] He argued the Conservative-led coalition government should revise its programme of fiscal consolidation, take a tougher stance with the British banking industry and take action to transform the credit ratings agency market.

[30] Umunna was promoted as Shadow Business Secretary on 7 October 2011, replacing John Denham, who announced his retirement from front-bench politics.

[32] During 2013, Umunna led claims that the Government's valuation of the Royal Mail during its privatisation had effectively "shortchanged" the taxpayer, a view supported by the significant rise in the share price following the sale and the subsequent summoning of bankers to a parliamentary investigation.

[35][36][37] Whilst a member of LFI, he condemned Israel's military courts for their treatment of Palestinian children accused of combat offences in December 2013.

[38] In April 2013, Umunna's law firm was linked to favourable updates made on his Wikipedia page in 2007, which included a reference to him being tipped as the "British Barack Obama".

[39][40] In the same month, Umunna was criticised for comments he had made in his mid 20s on the exclusive social network ASmallWorld about the West End of London.

[41] Umunna was accused of hypocrisy for accepting a £20,000 gift from a gambling executive despite campaigning against the spread of betting shops in his constituency and promising new powers to limit them.

[42] In early May 2014, Umunna raised concerns in Parliament[43] and public over the proposed takeover of AstraZeneca, by the American pharmaceutical giant Pfizer, on the grounds of ensuring British jobs and interests.

[46] In May 2014, Umunna criticised fellow Shadow Health Secretary Andy Burnham's report into possible methods of restricting the sale and advertising of alcohol, unhealthy foods, and tobacco.

[58] In September 2015, following the election of Jeremy Corbyn as the Leader of the Labour Party, Umunna announced his resignation from the Shadow Cabinet and returned to the backbenches, citing differences over the Brexit referendum and issues of collective ministerial responsibility.

People voted to leave and to remain for very different reasons, but it's nonsense to say that every single person who voted for Brexit in the EU referendum did so because they unanimously agreed on leaving the single market and the customs union, putting the Good Friday Agreement at risk, garnering no extra money for the NHS (contrary to what they were told) and potentially continuing years of austerity.

"[69] In August 2018, The Guardian reported that "Umunna and fellow Labour MP Chris Leslie are widely believed to be laying the groundwork for the creation of a new [political] party although both have denied this.

[71] On 18 February 2019, Umunna and six other MPs (Luciana Berger, Chris Leslie, Angela Smith, Mike Gapes, Gavin Shuker, and Ann Coffey) quit Labour in protest at Jeremy Corbyn's leadership to form The Independent Group (later Change UK).

[74] On 24 May 2019, Umunna wrote in the i newspaper that Change UK would be open to a pro-EU pact with the Liberal Democrats in order to unite the Remain vote.

He also said he "massively underestimated just how difficult it is to set up a fully fledged new party without an existing infrastructure", after Change UK received a mere 3.4% of the vote in the EU elections, far behind the Liberal Democrats' 20%.

[83] Though Umunna had previously been publicly critical of the Liberal Democrats for "enabling Tory austerity" during the 2010 to 2015 coalition government, he told the BBC that "things have changed."

[84] In September 2019, in his first major speech to the Liberal Democrat Federal Conference, Umunna argued Britain was unable to exert its moral authority against authoritarian leaders in the world at a time when Prime Minister Boris Johnson was threatening to break the law over Brexit.

[85] At the 2019 general election, Umunna stood in Cities of London and Westminster, and lost to the Conservative Party candidate, Nickie Aiken, finishing second with 30.7%.

Umunna said about the appointment "If we're to fundamentally change the model of capitalism we've got to ensure that the overwhelming majority of businesses are integrating ESG factors into corporate decision making like never before.