[1][2][3] Born in Bethnal Green, London, he was the son of Eugene Bernard Bellenger, a dairyman, and his wife Isabella Annette née Henner.

He worked in various jobs: in a tea warehouse in Houndsditch, as a messenger boy for the Post Office and as a clerk to an export company in the City of London.

He became active in the local Conservative Association, and was elected to Fulham Borough Council as a Municipal Reform Party councillor representing Baron's Court ward in 1922 and 1925.

[2][3] In June 1930, Bellenger was selected by the Labour Party as their prospective parliamentary candidate at Bethnal Green South West, but withdrew his candidature a year later on health grounds.

He returned to the United Kingdom briefly in May to take part in the Norway Debate in the Commons that led to the fall of Neville Chamberlain's government.

[2][3] When the Labour Party returned to government with a landslide at the 1945 general election, Bellenger was appointed Financial Secretary to the War Office.

He became increasingly disconnected from the mainstream of the party, being unsympathetic to trade unions, opposing the decriminalisation of homosexuality and supported the Unilateral Declaration of Independence by white Rhodesians.