McDonnell was born in Liverpool to a family with an Irish Catholic background.[8] He moved with his family to East Anglia when he was very young; his father became a bus driver and was a branch secretary of the Transport and General Workers' Union.[2][9] McDonnell attended Great Yarmouth Grammar School.[10] McDonnell began training to be a Catholic priest, receiving a Church grant to attend St Joseph's College, Ipswich,[11] a Roman Catholic boarding fee-paying independent school for boys (now co-educational), before eventually deciding against the vocation at the age of 15 or 16 as he "basically discovered girlfriends, so celibacy wasn't going to be an option. I was also into politics."[12] McDonnell is now irreligious, but refers to himself as a "cultural Catholic" and is a regular churchgoer.[12]
Upon leaving education, McDonnell held a series of unskilled jobs. After marrying his first wife, he studied for A-levels at night school at Burnley Technical College, and at the age of 23, he moved to Hayes in Greater London, attended Brunel University, and earned a bachelor's degree in government and politics.[13][14] During this period, he helped his wife run a small children's home in Hayes, and was active on behalf of his local community and for National Union of Public Employees. After completing his master's degree in politics and sociology at Birkbeck, University of London,[14][15] he became a researcher and official with the National Union of Mineworkers from 1977 to 1978, and later the Trades Union Congress from 1978 until 1982. From 1985 to 1987, McDonnell was head of the policy unit at Camden Borough Council, then chief executive of the Association of London Authorities from 1987 to 1995, and the Association of London Government from 1995 until 1997.[16]
...this is from Wikipedia; so, if it's on there it's hardly a secret. There was a man in our village who had the poshest of posh accents. He told me his father had died when he was young and because of this, as the eldest boy he was sent to a very posh private school. I think his father might have been in the forces but I'm not sure. I think it rather alienated him from the rest of his family. I hadn't realised till then that some children from poor families were sometimes sent to private schools.