He was educated in Trinidad, in a school at Higham Hill also attended by Benjamin Disraeli, at Charterhouse, and at Trinity College, Cambridge, where he graduated in 1830.

[1] In 1837, Gibson was elected to parliament as Conservative member for Ipswich, but resigned two years later and losing the subsequent by-election, having adopted Liberal views, and became an ardent supporter of the free-trade movement.

As one of Richard Cobden's chief allies, he was elected to the House of Commons as Member of Parliament for Manchester in 1841, and, from 1846 to 1848, he was Vice-President of the Board of Trade in Lord John Russell's ministry.

[3] Gibson was the leading spirit in the movement for the repeal of taxes on knowledge, and his successful efforts on behalf of journalism and advertising were recognized by a public testimonial in 1862.

Milner Gibson died on board his yacht, the Resolute, at Algiers on 25 February 1884, aged 77, and was buried in St. Peter's churchyard at Theberton in Suffolk on 13 March.