[3] Cruddas was educated at the Oaklands Roman Catholic Comprehensive School, Waterlooville, Portsmouth, before attending the University of Warwick where he ultimately received an M.A.

and a Ph.D. in Industrial and Business Studies in 1991, writing a thesis entitled An analysis of value theory, the sphere of production and contemporary approaches to the reorganisation of workplace relations.

Cruddas was selected to be the prospective parliamentary candidate for the safe Labour seat of Dagenham in 2000, after the sitting MP Judith Church announced that she would be retiring.

From the backbenches, Cruddas quickly became a vocal critic of the government for what he saw as their ignoring of their traditional, working-class support in a bid to be more appealing to middle-class voters.

[12] On 27 September 2006, Cruddas announced his intention to stand to become Deputy Leader of the Labour Party once the incumbent, John Prescott, stood down.

[14] In interviews, Cruddas also said that he did not want the "trappings or baubles" that would potentially come with the job of Deputy Prime Minister, such as use of the Dorneywood weekend country residence.

[16] He received backing from former Deputy Leader Roy Hattersley,[17] then Mayor of London Ken Livingstone,[18] NUS President Gemma Tumelty, and former National Executive Committee member, actor and presenter Tony Robinson.

[21] In 2012, Cruddas was appointed to Ed Miliband's Shadow Cabinet, replacing Liam Byrne as Labour Party Policy Coordinator.

The goal of the commission is to make a set of achievable policy recommendations, which will be delivered in a report in September 2017 at Labour Annual Conference in Brighton.

[23] Cruddas narrowly retained his seat at the 2019 general election, with a hugely reduced majority, winning by 293 votes over the Conservative candidate.

[27] Cruddas's deputy leadership challenge was based on the precepts contained in a pamphlet called 'Fit for purpose: A programme for Labour Party renewal', co-authored with journalist John Harris and funded by the pressure group Compass.

[28] Cruddas won a Compass membership poll in March 2007, gaining 53% of first preference votes among the deputy leadership candidates.

[39] In 2023 Cruddas publicly revealed his opposition to expansion of the Ultra Low Emission Zone (ULEZ) by the Mayor of London Sadiq Khan, calling it "an unwelcome hit on working people".